The Perils Of Iodine Deficiency For Women

Where Can You Get The Iodine You Need?

Author: Dr. Stephen Chaney

SaltIt shouldn’t be happening. The introduction of iodized salt in the 1920s virtually eliminated iodine deficiency in this country. However, in just the past twenty years the incidence of iodine deficiency has increased 3-8-fold in women of childbearing age. Recent studies have estimated that today 30-40% of women of childbearing age are iodine deficient.

How did that happen?

  • We have been told to cut back on sodium. Many Americans have responded by throwing away the (iodized) salt shaker. Unfortunately, we still get a lot of salt from processed foods, and that salt is usually non-iodized.
  • When we do add salt to our foods it is usually the “healthier” designer salts. First it was sea salt. Now it is trendy versions like Pink Himalayan Salt. While sea salt might have some iodine naturally, the trendier versions are non-iodized.

The consequences of iodine deficiency, especially among women of childbearing age, are alarming. In a previous issue of “Health Tips From the Professor” I reported that iodine is essential for bone and neural development during fetal development and infancy.

This study (JL Mills et al, Human Reproduction, doi: 10.1093/humrep/dex379, 2018) reports that iodine deficiency also reduces a woman’s chances of becoming pregnant.

How Was The Study Done?

Clinical StudyThis study recruited 501 couples (ages 18-40) from 16 counties in Michigan and Texas. The women had all discontinued conception within the previous two months with the intention of becoming pregnant and were followed for an additional 12 months. Women with known thyroid disease were excluded from the study.

Urine samples were collected from each woman at the beginning of the study to determine iodine and creatine levels. The women used fertility monitors to time intercourse relative to ovulation (Basically, that means they optimized their chances of becoming pregnant). They then used digital home pregnancy monitors on the day of expected menstruation to identify pregnancies.

Finally, 90% of the women took either a multivitamin or a prenatal vitamin during the study (The significance of this will be discussed later).

The Perils Of Iodine Deficiency For Women

healthy pregnancyThe results of the study were:

  • 44.3% of the women in the study were iodine deficient (defined as iodine-creatine ratios of <100 mcg/g). This was further broken down to:
    • 21.8% were mildly iodine deficient (50-99 mcg/g).
    • 20.8% were moderately iodine deficient (20-49 mcg/g).
    • 1.7% were severely iodine deficient (<20 mcg/g).
  • That is a total of 22.5% who had moderate to severe iodine deficiency.
  • Women who had moderate to severe iodine deficiency had a 46% decrease in the chance of becoming pregnant over each menstrual cycle compared to the iodine sufficient group.

A simple way of reporting those data would be to say that their chances of becoming pregnant were reduced by 46%, but that would not convey the whole picture. Most of the women did become pregnant during the 12-month study. However, it took the women with moderate to severe iodine deficiency twice as long to become pregnant. Iodine deficiency did not prevent pregnancy from occurring, but it delayed it.

The authors concluded: “In summary, our data show that groups of women with iodine concentrations in the moderate to severe deficient range experience a significantly longer time to pregnancy…The US and European countries where iodine deficiency is common should evaluate the need for programs to increase iodine intake for women of childbearing age, particularly those trying to become pregnant.”

And the increased difficulty in becoming pregnant is just the tip of the iceberg. As I mentioned above, the consequences of iodine deficiency among women of childbearing age, can be devastating.

Iodine is essential for bone and neural development during fetal development and infancy. The American Academy of Pediatrics, The National Institutes Of Health, and the World Health Organization have all declared that mild iodine deficiency during pregnancy can prevent normal cognitive development and reduce IQ levels in children.

Because the consequences of iodine deficiency during pregnancy are so detrimental, if iodine deficiency also reduced the chances of a woman becoming pregnant, it could be considered a good thing. It could be part of Nature’s Plan. Unfortunately, this study suggests that iodine deficiency only delays pregnancy. It doesn’t prevent it.

Where Can You Get The Iodine You Need?

SeaweedSince iodine is so essential for a healthy pregnancy, the important question becomes: “Where can you get the iodine you need?”

  • You could start by using old-fashioned iodized salt rather than designer salts in your salt shaker. However, I am reluctant to recommend anything that would increase sodium intake. We get far too much from processed foods already.
  • Seafood (or seaweed, if you are a vegetarian) are the best food sources of iodine. However, our oceans are so contaminated I would recommend consuming those foods only occasionally.
  • You will often see bread and dairy mentioned as good food sources because iodine was used in the preparation of those foods. However, iodine has largely been replaced by other agents, so those foods should no longer be considered good sources. For example:
    • Iodine in commercial breads has traditionally come from the use of iodate as a dough conditioner. Today iodate has largely been replaced with bromide in commercial bread making. Not only does this trend decrease the amount of iodine available in our diet, but bromide also interferes with iodine utilization in our bodies
    • Iodine in milk has traditionally come from the use of iodine-containing disinfectants to clean milk cans and teats. However, they have largely been replaced with other disinfectants
  • Fruits and vegetables are a variable source of iodine, depending on where they were grown. That is because iodine levels in the soils vary tremendously from region to region.
  • That leaves multivitamins and prenatal vitamins as your best source. However, you do need to read labels. You should look for supplements that provide 150 mcg of iodine. Unfortunately, only 50% of prenatal supplements in the United States even contain iodine. Remember, 90% of the women in this study took either a multivitamin or prenatal supplement and 44.3% of them were iodine deficient.

The Bottom Line

The introduction of iodized salt in the 1920s virtually eliminated iodine deficiency in this country. Now, almost 100 years later, iodine deficiency is back. Recent studies estimate that 30-40% of women of childbearing age are iodine deficient. This is concerning. Previous studies have shown iodine deficiency affects mental development during fetal development and infancy. A recent study suggests that iodine deficiency may also make it more difficult for women to become pregnant. Specifically, the study reported:

  • 44.3% of the women in the study were iodine deficient. This was further broken down to:
    • 21.8% were mildly iodine deficient.
    • 20.8% were moderately iodine deficient.
    • 1.7% were severely iodine deficient.
  • That is a total of 22.5% with moderate to severe iodine deficiency.
  • Women who had moderate to severe iodine deficiency had a 46% decrease in their chance of becoming pregnant over each menstrual cycle compared to the iodine sufficient group.

A simple way of reporting those data would be to say that their chances of becoming pregnant were reduced by 46%, but that would not convey the whole picture. Most of the women did become pregnant during the 12-month study. However, it took the women with moderate to severe iodine deficiency twice as long to become pregnant. Iodine deficiency did not prevent pregnancy from occurring, but it delayed it.

For more details about why iodine deficiency has reemerged in this country and where we can get the iodine we need, read the article above.

These statements have not been evaluated by the Food and Drug Administration. This information is not intended to diagnose, treat, cure or prevent any disease.

How Much Omega-3 Should You Take During Pregnancy?

Which Omega-3s Are Beneficial? 

Author: Dr. Stephen Chaney

Premature BabyPreterm births (births occurring before 37 weeks) are increasing in this country. Just between 2018 and 2019, the percentage of preterm births increased by 2% to over 10% of all pregnancies. That is a concern because preterm births are associated with an increased risk of:

  • Visual impairment.
  • Developmental delays.
  • Learning difficulties.
  • Problems with normal development of lungs, eyes, and other organs.

Plus, it is expensive to keep premature babies alive. One recent study estimated that reducing the incidence of preterm births by around 50% could reduce health care costs by $6 billion in the United Stated alone.

Of the 10% preterm births, 2.75% of them are early preterm births (births occurring before 34 weeks). Obviously, the risk of health problems and the cost of keeping them alive is greatest for early preterm babies.

We don’t know why preterm births are increasing, but some experts feel it is because in this country:

  • More older women are having babies.
  • There is increased use of fertility drugs, resulting in multiple babies

Unfortunately, there is no medical standard for identifying pregnancies at risk for preterm birth. Nor is there any agreement around prevention measures for preterm births.

However, recent research has suggested that some premature births may be caused by inadequate omega-3 status in the mother and can be prevented by omega-3 supplementation.

What Do We Know About Omega-3s And Risk Of Preterm Births?

omega-3s during pregnancy is healthyThe role of omega-3s on a healthy pregnancy has been in the news for some time. Claims have been made that omega-3s reduce preterm births, postnatal depression, and improve cognition, IQ, vision, mental focus, language, and behavior in the newborn as they grow.

The problem is that almost all these claims have been called into question by other studies. If you are pregnant or thinking of becoming pregnant, you don’t know what to believe.

Fortunately, a group called the Cochrane Collaboration has recently reviewed these studies. The Cochrane Collaboration consists of 30,000 volunteer scientific experts from across the globe whose sole mission is to analyze the scientific literature and publish reviews of health claims so that health professionals, patients, and policy makers can make evidence-based choices about health interventions. Their reviews are considered the gold standard of evidence-based medicine.

This is because most published meta-analyses simply report “statistically significant” conclusions. However, statistics can be misleading. As Mark Twain said: “There are lies. There are damn lies. And then there are statistics”.

The problem is the authors of most meta-analyses group studies together without considering the quality of studies included in their analysis. This creates a “Garbage In – Garbage Out” effect. If the quality of individual studies is low, the quality of the meta-analysis will also be low.

The Cochrane Collaboration reviews are different. They also report statistically significant conclusions from their meta-analyses. However, they carefully consider the quality of each individual study in their analysis. They look at possible sources of bias. They look at the design and size of the studies. Finally, they ask whether the conclusions are consistent from one study to the next. They clearly define the quality of evidence that backs up each of their conclusions.

For omega-3s and pregnancy, the Cochrane Collaboration performed a meta-analysis and review of 70 randomized controlled trials that compared the effect of added omega-3s on pregnancy outcomes with the effect of either a placebo or no omega-3s. These trials included almost 19,927 pregnant women.

This Cochrane Collaboration Review looked at all the claims for omega-3s and pregnancy outcome, but they concluded that only two of the claims were supported by high-quality evidence:

  • Omega-3s reduce the risk of preterm births.
  • Omega-3s reduce the risk of low birth-weight infants.

The authors concluded: “Omega-3 supplementation during pregnancy is an effective strategy for reducing the riskclinically proven of preterm birth…More studies comparing [the effect of] omega-3s and placebo [on preterm births] are not needed at this point.”

In other words, they are saying this conclusion is definite. The Cochrane Collaboration has declared that omega-3 supplementation should become part of the standard of medical care for pregnant women.

However, the Cochrane Collaboration did say that further studies were needed “…to establish if, and how, outcomes vary by different types of omega-3s, timing [stage of pregnancy], doses [of omega-3s], or by characteristics of women.”

That’s because these variables were not analyzed in this study. The study included clinical trials:

  • Of women at low, moderate, and high risk of poor pregnancy outcomes.
  • With DHA alone, with EPA alone, and with a mixture of both.
  • Omega-3 doses that were low (˂ 500 mg/day), moderate (500-1,000 mg/day), and high (> 1,000 mg/day).

I have discussed these findings in more detail in a previous issue of “Health Tips From The Professor”

How Was This Study Done?

Clinical StudyThe current study (SE Carlson et al, EClinicalMedicine, 2021) is a first step towards answering those questions.

The authors of this study focused on how much DHA supplementation is optimal during pregnancy. This is an important question because there is currently great uncertainty about how much DHA is optimal:

  • The American College of Obstetrics and Gynecology recommends supplementation with 200 mg/day of DHA. However, that recommendation assumes that the increase will come from fish and was influenced by concerns that omega-3-rich fish are highly contaminated with heavy metals and PCBs.
  • Another group of experts was recently asked to develop guidelines for omega-3 supplementation during pregnancy. They recommended pregnant women consume at least 300 mg/day of DHA and 220 mg/day of EPA.
  • The WHO has recommended of minimum dose of 1,000 mg of DHA during pregnancy.
  • Many prenatal supplements now contain 200 mg of DHA, but very few provide more than 200 mg.

Accordingly, the authors took the highest and lowest recommendations for DHA supplementation and asked whether 1,000 mg of DHA per day was more effective than 200 mg of DHA at reducing the risk of early preterm births. Their hypothesis was that 1,000 mg of DHA would be more effective than 200 mg/day at preventing early preterm births.

This study was a multicenter, double-blind, randomized trial of 1032 women recruited at one of three large academic medical centers in the United States (University of Kansa, Ohio State University, and University of Cincinnati).

  • The women were ≥ 18 years old (average age = 30) and between 12 and 20 weeks of gestation when they entered the study.
  • The breakdown by ethnicity was 50% White, 22% Black or African American, 22% Hispanic, 6% Other.
  • 18% had a prior preterm birth (<37 weeks) and 7% had a prior early preterm birth (<34 weeks).
  • Prior to enrollment in the study 47% of the participants reported taking a DHA supplement and 19% of the participants took a DHA supplement with > 200 mg/day.

All the participants received 200 mg DHA capsules and were told to take one capsule daily. The participants were also randomly assigned to take 2 additional capsules that contained a mixture of corn and soybean oil (the 200 mg DHA/day group) or 2 capsules that contained 400 mg of DHA (the 1,000 mg DHA/day group). The capsules were orange flavored so the participants could not distinguish between the DHA capsules and the placebo capsules.

Blood samples were drawn upon entry to the study and either just prior to delivery or the day after delivery to determine maternal DHA status.

The study was designed to look at the effect of DHA dose (1,000 mg or 200 mg) on early preterm birth (<34 weeks), preterm birth (<37 weeks), low birth weight (< 3 pounds), and several other parameters related to maternal and neonatal health.

How Much Omega-3 Should You Take During Pregnancy?

pregnant women taking omega-3The primary findings from this study were:

  • The rate of early preterm births (<34 weeks) was less (1.7%) for pregnant women taking 1,000 mg of DHA/day compared to 200 mg/day (2.4%).
  • The rate of late preterm births (between 34 and 37 weeks) was also less for women taking 1,000 mg of DHA/day compared to 200 mg/day.
  • Finally, low birth weight and the frequency of several maternal and neonatal complications during pregnancy, delivery, and immediately after delivery were also lower with 1,000 mg/day of supplemental DHA than with 200 mg/day.

This confirms the authors’ hypothesis that supplementation with 1,000 mg/day of DHA is more effective than 200 mg/day at reducing the risk of early preterm births. In addition, this study showed that supplementation with 1,000 mg of DHA/day had additional benefits.

This study did not have a control group receiving no DHA. However:

  • The US average for early preterm births is 2.74%.
  • For the women in this study who had previous pregnancies, the rate of early preterm birth was 7%.

Of course, the important question for any study of this type is whether all the women benefited equally from supplementation. Fortunately, this study was designed to answer that question.

As noted above, each woman was asked whether they took any DHA supplements at the time they enrolled in the study, and 47% of the women in the study were taking DHA supplements when they enrolled. In addition, the DHA status of each participant was determined from blood samples taken at the time the women were enrolled in the study. When the authors split the women into groups based on their DHA status at the beginning of the study:

  • For women with low DHA status the rate of early preterm births was 2.0% at 1,000 mg of DHA/day versus 4.1% at 200 mg of DHA/day.
  • For women with high DHA status the rate of early preterm births was around 1% for both 1,000 mg of DHA/day and 200 mg of DHA/day.

In other words, DHA supplementation only appeared to help women with low DHA status. This is good news because:

  • DHA status is an easy to measure predictor of women who are at increased risk of early preterm birth.
  • This study shows that supplementation with 1,000 mg of DHA/day is effective at reducing the risk of early premature birth for women who are DHA deficient.

In the words of the authors, “Clinicians could consider prescribing 1,000 mg DHA daily during pregnancy to reduce early preterm birth in women with low DHA status if they are able to screen for DHA.”

Which Omega-3s Are Beneficial?

DHA is the most frequently recommended omega-3 supplement during pregnancy.

It is not difficult to understand why that is.

  • DHA is a major component of the myelin sheath that coats every neuron in the brain. [You can think of the myelin sheath as analogous to the plastic coating on a copper wire that allows it to transmit electricity from one end of the wire to the other.]
  • Unlike other components of the myelin sheath, the body cannot make DHA. It must be provided by the diet.
  • During the third trimester, DHA accumulates in the human brain faster than any other fatty acid.
  • Animal studies show that DHA deficiency during pregnancy interferes with normal brain and eye development.
  • Some, but not all, human clinical trials show that DHA supplementation during pregnancy improves developmental and cognitive outcomes in the newborn.
  • Recent studies have shown that most women in the United States only get 60-90 mg/day of DHA in their diet.

Clearly, DHA is important for fetal brain development during pregnancy, and most pregnant women are not getting enough DHA in their diet. This is why most experts recommend supplementation with DHA during pregnancy. And this study suggests supplementation with 1,000 mg/day is better than 200 mg/day. However, two important questions remain:Questioning Woman

#1: Is 1,000 mg of DHA/day optimal? The answer is, “We don’t know”. This study compared the highest recommended dose (1,000 mg/day) with the lowest recommended dose (200mg/day) and concluded that 1,000 mg/day was better than 200 mg/day.

But would 500 or 800 mg/day be just as good as 1,000 mg/day? We don’t know. More studies are needed.

#2: Can DHA do it all, or are other omega-3s also important for a healthy pregnancy? As noted above, the emphasis on supplementation with DHA was based on the evidence for a role of DHA in fetal brain development during pregnancy.

But is DHA or EPA more effective at preventing early preterm birth and maternal pregnancy complications? Again, we don’t know.

As noted above, the Cochrane Collaboration concluded that omega-3s were effective at reducing early preterm births but was unable to evaluate the relative effectiveness of EPA and DHA because their review included studies with DHA only, EPA only, and EPA + DHA.

This is an important question because the ability of the body to convert EPA to DHA and vice versa is limited (in the 10-20%) range. This means that if both EPA and DHA are important for a healthy pregnancy, it might not be optimal to supplement with a pure DHA or pure EPA supplement.

Based on currently available data if you are pregnant or thinking of becoming pregnant, my  recommendations are:

  • Chose a supplement that provides both EPA and DHA.
  • Because the evidence is strongest for DHA at this time, chose an algal source of omega-3s that has more DHA than EPA.
  • Aim for a dose of DHA in the 500 mg/day to 1,000 mg/day range. Remember, this study showed 1,000 mg/day was better than 200 mg/day but did not test whether 500 or 800 mg/day might have been just as good.

As more data become available, I will update my recommendations.

The Bottom Line

The Cochrane Collaboration recently released a report saying that the evidence was definitive that omega-3 supplementation during pregnancy reduced the risk of early preterm births. However, they were not able to reach a definitive conclusion on the optimal dose of omega-3s or the relative importance of EPA and DHA at preventing early preterm birth.

Most experts recommend that pregnant women supplement with between 200 mg/day and 1,000 mg/day of DHA.

A recent study asked whether 1,000 mg of DHA/day was better than 200 mg/day at reducing the risk of early preterm birth. The study found:

  • The rate of early preterm births (<34 weeks) was less (1.7%) for pregnant women taking 1,000 mg of DHA/day than pregnant women taking 200 mg/day (2.4%).
  • For women with low DHA status at the beginning of the study, the rate of early preterm births was 2.0% at 1,000 mg of DHA/day versus 4.1% at 200 mg of DHA/day.
  • For women with high DHA status at the beginning of the study, the rate of early preterm births was around 1% for both 1,000 mg of DHA/day and 200 mg of DHA/day.

The authors concluded, “Clinicians could consider prescribing 1,000 mg DHA daily during pregnancy to reduce early preterm birth in women with low DHA status…”

There are two important caveats:

  • This study did not establish the optimal dose of DHA. The study concluded that 1,000 mg/day was better than 200 mg/day. But would 500 or 800 mg/day be just as good as 1,000 mg/day? We don’t know. More studies are needed.
  • This study did not establish the relative importance of EPA and DHA for reducing the risk of early preterm births. DHA is recommended for pregnant women based on its importance for fetal brain development. But is DHA more important than EPA for reducing the risk of early preterm births? Again, we don’t know. More studies are needed.

For more details about this study and my recommendations, read the article above.

These statements have not been evaluated by the Food and Drug Administration. This information is not intended to diagnose, treat, cure, or prevent any disease.

Does Maternal Vitamin D Affect Childhood ADHD?

Can ADHD Be Prevented?

vitamin dIf you are pregnant, or of childbearing age, should you be supplementing with vitamin D? Increasingly, the answer appears to be yes.

1) Based on blood 25-hydroxy vitamin D levels (considered the most accurate marker of vitamin D status):

    • 8-11% of pregnant women in the US are deficient in vitamin D (<30 nmol/L).
    • 25% of pregnant women have insufficient vitamin D status (30-49 nmol/L).

In short, that means around 1/3 of pregnant women in the US have insufficient or deficient levels of vitamin D. The effect of inadequate vitamin D during pregnancy is not just an academic question.

2) The Cochrane Collaboration (considered the gold standard for evidence-based medicine) has recently concluded that supplementation with vitamin D reduces the risk of significant complications during pregnancy.

3) Another recent study found that inadequate vitamin D status during pregnancy delayed several neurodevelopmental milestones in early childhood, including gross motor skills, fine motor skills, and social development.

If neurodevelopmental milestones are affected, what about ADHD? Here the evidence is not as clear. Some studies have concluded that vitamin D deficiency during pregnancy increases the risk of ADHD in the offspring. Other studies have concluded there is no effect of vitamin D deficiency on ADHD.

Why the discrepancy between studies?

  • Most of the previous studies have been small. Simply put, there were too few children in the study to make statistically reliable conclusions.
  • Most of the studies measured maternal 25-hydroxyvitamin D levels in the third trimester or in chord blood at birth. However, it is during early pregnancy that critical steps in the development of the nervous system take place.

Thus, there is a critical need for larger studies that measure maternal vitamin D status in the first trimester of pregnancy. This study (M Sucksdorff et al, Journal of the American Academy of Child & Adolescent Psychiatry, 2020, in press) was designed to fill that need.

How Was The Study Done?

Clinical StudyThis study compared 1,067 Finnish children born between 1998 and 1999 who were subsequently diagnosed with ADHD and 1,067 matched controls without ADHD. There were several reasons for choosing this experimental group.

  • Finland is among the northernmost European countries, so sun exposure during the winter is significantly less than for the United States and most other European countries. This time period also preceded the universal supplementation with vitamin D for pregnant women that was instituted in 2004.

Consequently, maternal 25-hydroxyvitamin D levels were significantly lower than in most other countries. This means that a significant percentage of pregnant women were deficient in vitamin D, something not seen in most other studies. For example:

    • 49% of pregnant women in Finland were deficient in vitamin D (25-hydoxyvitamin D <30 nmol/L) compared to 8-11% in the United States.
    • 33% of pregnant women in Finland had insufficient vitamin D status (25-hydroxyvitamin D 30-49.9 nmol/L) compared to 25% in the United States.
  • Finland, like many European countries, keeps detailed health records on its citizens. For example:
    • The Finnish Prenatal Study collected data, including maternal 25-hydroxyvitamin D levels during the first trimester), for all live births between 1991 and 2005.
    • The Care Register for Health Care recorded, among other things, all diagnoses of ADHD through 2011.

Thus, this study was ideally positioned to compare maternal 25-hydroxyvitamin D levels during the first trimester of pregnancy with a subsequent diagnosis of ADHD in the offspring. The long-term follow-up was important to this study because the average age of ADHD diagnosis was 7 years (range = 2-14 years).

Does Maternal Vitamin D Affect Childhood ADHD?

Child With ADHDThe answer to this question appears to be a clear, yes.

If you divide maternal vitamin D levels into quintiles:

  • Offspring of mothers in the lowest vitamin D quintile (25-hydroxyvitamin D of 7.5-21.9 nmol/L) were 53% more likely to develop ADHD than offspring of mothers in the highest vitamin D quintile (49.5-132.5 nmol/L).

When you divide maternal vitamin D levels by the standard designations of deficient (<30 nmol/L), insufficient (30-49.9 nmol/L), and sufficient (≥50 nmol/L):

  • Offspring of mothers who were deficient in vitamin D were 34% more likely to develop ADHD than children of mothers with sufficient vitamin D status.

The authors concluded: “This is the first population-based study to demonstrate an association between low maternal vitamin D during the first trimester of pregnancy and an elevated risk for ADHD diagnosis in offspring. If these findings are replicated, they may have public health implications for vitamin D supplementation and perhaps changing lifestyle behaviors during pregnancy to ensure optimal maternal vitamin D levels.”

Can ADHD Be Prevented?

Child Raising HandI realize that this is an emotionally charged title. If you have a child with ADHD, the last thing I want is for you to feel guilty about something you may not have done. So, let me start by acknowledging that there are genetic and environmental risk factors for ADHD that you cannot control. That means you could have done everything right during pregnancy and still have a child who develops ADHD.

Having said that, let’s examine things that can be done to reduce the risk of giving birth to a child who will develop ADHD, starting with vitamin D. There are two aspects of this study that are important to keep in mind.

#1: The increased risk of giving birth to a child who develops ADHD was only seen for women who were vitamin D deficient. While vitamin D deficiency is only found in 8-11% of pregnant mothers in the United States, that is an average number. It is more useful to ask who is most likely to be vitamin D deficient in this country. For example:

  • Fatty fish and vitamin D-fortified dairy products are the most important food sources of vitamin D. Fatty fish are not everyone’s favorite and may be too expensive for those on a tight budget. Many people are lactose intolerant or avoid milk for other reasons. If you are not eating these foods, you may not be getting enough vitamin D from your diet. This is particularly true for vegans.
  • If you have darker colored skin, you may have trouble making enough vitamin D from sunlight. If you are also lactose intolerant, you are in double trouble with respect to vitamin D sufficiency.
  • Obesity affects the distribution of vitamin D in the body. So, if you are overweight, you may have low 25-hydroxyvitamin D levels in your blood.
  • The vitamin D RDA for pregnant and lactating women is 600 IU, but many multivitamin and prenatal supplements only provide 400 IU. If you are pregnant or of childbearing age, it is a good idea to look for a multivitamin or prenatal supplement that provides at least 600 IU, especially if you are in one of the high risk groups listed above.
  • Some experts recommend 2,000 to 4,000 IU of supplemental vitamin D. I would not recommend exceeding that amount without discussing it with your health care provider first.
  • Finally, for reasons we do not understand, some people have a difficult time converting vitamin D to the active 25-hydroxyvitamin D and 1,25-dihydroxyvitamin D in their bodies. If you are pregnant or of childbearing age, it is a good idea to have your blood 25-hydroxyvitamin D levels determined and discuss with your health care provider how much vitamin D you should be taking. Many people need more than 600 IU to reach vitamin D sufficiency status.

#2: Maternal vitamin D deficiency has a relatively small effect (34%) on the risk of the offspring developing ADHD. That means assuring adequate vitamin D status during pregnancy should be part of a holistic approach for reducing ADHD risk. Other factors to consider are:

  • Low maternal folate and omega-3 status.
  • Smoking, drug, and alcohol use.
  • Obesity.
  • Sodas and highly processed foods.

Alone, each of these factors has a small and uncertain influence on the risk of your child developing ADHD. Together, they may play a significant role in determining your child’s risk of developing ADHD.

In closing, there are three take-home lessons I want to leave you with:

1) The first is that there is no “magic bullet”. There is no single action you can take during pregnancy that will dramatically reduce your risk of giving birth to a child who will develop ADHD. Improving your vitamin D, folate, and omega-3 status; avoiding cigarettes, drugs, and alcohol; achieving a healthy weight; and eating a healthy diet are all part of a holistic approach for reducing the risk of your child developing ADHD.

2) The second is that we should not think of these actions solely in terms of reducing ADHD risk. Each of these actions will lead to a healthier pregnancy and a healthier child in many other ways.

3) Finally, if you have a child with ADHD and would like to reduce the symptoms without drugs, I recommend this article.

The Bottom Line

A recent study looked at the correlation between maternal vitamin D status during the first trimester of pregnancy and the risk of ADHD in the offspring. The study found:

  • Offspring of mothers who were deficient in vitamin D were 34% more likely to develop ADHD than children of mothers with sufficient vitamin D status.

The authors concluded: “This is the first population-based study to demonstrate an association between low maternal vitamin D during the first trimester of pregnancy and an elevated risk for ADHD diagnosis in offspring. If these findings are replicated, they may have public health implications for vitamin D supplementation and perhaps changing lifestyle behaviors during pregnancy to ensure optimal maternal vitamin D levels.”

In the article above I discuss what this study means for you and other factors that increase the risk of giving birth to a child who will develop ADHD.

For more details read the article above.

These statements have not been evaluated by the Food and Drug Administration. This information is not intended to diagnose, treat, cure, or prevent any disease.

 

Are Pregnant Women and Children Dangerously Deficient in Omega-3s?

What Is The Omega-3 Status Of The American Population?

Author: Dr. Stephen Chaney

 

pregnant women omega 3 deficient fishIt is no secret that the American population is deficient in omega-3s. Numerous studies have documented that fact. There are many reasons for Americans’ low intake of omega-3s:

  • The high price of omega-3-rich fish.
  • Concerns about sustainability, heavy metal contamination, and/or PCB contamination of omega-3 rich fish.
  • Misleading headlines claiming that omega-3 supplements are worthless and may even do you harm.

Of course, the questions you are asking are probably?

  • How deficient are we?
  • Does it matter?

The latest study (M Thompson et al, Nutrients, 2019, 11: 177, doi: 10.3390/nu11010177) goes a long way towards answering those important questions.

How Was The Study Done?

scientific studyThis study used data on 45,347 Americans who participated in NHANES surveys between 2003 and 2014. (NHANES or National Health and Nutrition Examination Surveys is a program run by the CDC that is designed to assess the health and nutritional status of adults and children living in the United States).

EPA and DHA intake from foods was based on the average of two 24-hour dietary recall interviews. Trained dietary interviewers collected detailed information on all foods and beverages consumed during the past 24 hours.

To assess EPA and DHA intake from supplements study participants were asked what supplements they had taken in the past 30 days, how many days out of 30 they had taken it, and the amount that was taken on those days.

 

What Is The Omega-3 Status Of The American Population?

 

omega 3 statusThe results of the NHANES surveys were shocking.

In terms of total EPA+DHA intake:

  • EPA+DHA intake across all age groups was lower than recommended.
  • Toddlers (ages 1-5), children (ages 6-11), and adolescents (ages 12-19) had lower EPA+DHA intakes than adults (ages 20-55) and seniors (ages > 55).
  • Women had lower EPA+DHA intakes than men.
  • Pregnant women and women of childbearing age did not differ in their EPA+DHA.
  • Pregnant women consumed less fish than women of childbearing age (perhaps because of concerns about heavy metal contamination).
  • Pregnant women consumed more omega-3 supplements.

In terms of EPA+DHA from supplements:

  • Less than 1% of the American population reported using omega-3 supplements.
  • The one exception was pregnant women. 7.3% of pregnant women reported taking an omega-3 supplement.
  • People taking omega-3 supplements had significantly higher EPA+DHA intake than people not taking omega-3 supplements.
  • This was also true for pregnant women. Those taking omega-3 supplements had higher EPA+DHA intake.

Of course, like any clinical study, it has strengths and weaknesses.

The biggest weakness of this study is that omega-3 intake is based on the participants recall of what they ate. The strengths of the study are its size (45,347 participants) and the fact that its estimate of omega-3 intake is consistent with several smaller studies.

 

Are Americans Deficient In Omega-3s?

 

pregnant women omega 3 deficient questionsNow we are ready to answer the questions I posed at the beginning of this article. Let’s start with the first one: “How deficient are we?”

You would think the answer to that question would be easy. It is not. This study provides a precise estimate of American’s omega-3 intake. The problem is there is no consensus as to how much omega-3s we need. There is no RDA for omega-3s.

There are, in fact, three sets of guidelines for how much omega-3s we need, and they disagree.

  • The World Health Organization (WHO) recommendations for EPA+DHA intake range from 100-150 mg/day at ages 2-4 years to 200-500 mg/day for adults.
  • The US National Institute of Medicine (IOM) recommendations for EPA+DHA intake range from 70 mg/day for ages 1-3 to 110 mg/day for adult females and 160 mg/day for adult males.
  • As if that weren’t confusing enough, an international group of experts recently convened for a “Workshop on the Essentiality of and Recommended Dietary Intakes for Omega-6 and Omega-3 Fatty Acids” (Workshop). This group recommended an EPA+DHA intake of 440 mg/day for adults and 520 mg/day for pregnant and lactating women.

Using these recommendations as guidelines, this study reported that:

  • EPA+DHA intake for children 1-5 years old was ~25% of the WHO recommendations and ~40% of IOM recommendations.
  • EPA+DHA intake for children 6-11 years old was ~27% of WHO recommendations and ~40% of IOM recommendations.
  • EPA+DHA intake for adolescents 12-19 years old was ~50% of IOM recommendations (The WHO did not have a separate category for adolescents.
  • EPA+DHA intake for adults 20-55 years old was ~30% of WHO recommendations, and ~65% of IOM recommendations.
  • EPA+DHA intake for seniors >55 years old was 38% of WHO recommendations and 82% of IOM recommendations.
  • EPA+DHA intake for pregnant women was ~20% of Workshop recommendations (The WHO and IOM did not have a separate category for pregnant women).

While the percentage deficiency varied according to the EPA+DHA guidelines used, it is clear from these results that Americans of all age groups are not getting enough omega-3s from their diet.

The authors concluded: “We found omega-3 intakes across all age groups was lower than recommended amounts.”

 

Are Pregnant Women and Young Children Dangerously Deficient In Omega-3s?

 

danger symbolWhile the authors concluded that all age groups were deficient in omega-3s, they were particularly concerned about the omega-3 deficiencies in pregnant women and young children.

The authors said: “Taken together, these findings demonstrate that low omega-3 fatty acid intake is consistent among the US population and could increase the risk for adverse health outcomes, particularly in vulnerable populations (e.g., young children and pregnant women).”

In part, the focus on young children and pregnant women was based on their very low omega-3 intake. With intakes at 20-27% of recommended levels, I would consider these groups to be dangerously deficient in omega-3s.

pregnant women omega 3 deficient pregnancyHowever, the focus on young children and pregnant women was also based on the seriousness of the adverse health outcomes associated with low omega-3 intake in these population groups. This answers the second question I posed at the beginning of this article: “Does it matter?”

According to the authors low intake of EPA and DHA during pregnancy and early childhood is associated with maternal depression, pre-term births, low birth-weight babies, increased risk of allergies and asthma, problems with learning and cognition, and other neurocognitive outcomes.

None of these associations between low omega-3 intake and adverse health outcomes have been proven beyond a shadow of a doubt, but the evidence is strong enough that we should be alarmed by the very low omega-3 intake in pregnant women and young children.

There is, however, a simple solution. The authors of this study concluded: “Individuals taking EPA/DHA containing supplements had significantly elevated intake compared to individuals not taking omega-3 fatty acid-containing supplements or not reporting any supplement use.”

omega 3 supplementsThey went on to say: “As supplement use is associated with increased omega-3 intake, supplementation could be an important source of EPA/DHA, particularly for pregnant women given their lower fish consumption compared to non-pregnant women of childbearing age.”

I agree. Given the low omega-3 intake in these population group and current guidelines for omega-3 intake. I recommend:

  • Pregnant & lactating women (and women of childbearing age who might become pregnant) take an omega-3 supplement providing around 520 mg of EPA+DHA/day.
  • Young children (ages 1-5) take an omega-3 supplement providing around 100 mg of DHA/day.

Of course, this study also confirmed that Americans of all age groups are not getting enough omega-3s from their diet, and low omega-3 intake may increase the risk of heart disease. Furthermore, recent studies have shown that high purity omega-3 supplements may reduce heart disease risk.

You will find my recommendations for omega-3 supplementation for adults in a previous issue of “Health Tips From the Professor.”

 

The Bottom Line

 

The largest study to date (45,347 participants) measured omega-3 intake for Americans of all ages and compared that to current recommendations for omega-3 intake.

The authors of the study concluded:

  • “We found omega-3 intakes across all age groups was lower than recommended amounts.”
  • “Low omega-3 fatty acid intake … could increase the risk for adverse health outcomes, particularly in vulnerable populations (e.g., young children and pregnant women.”

In part, the focus on young children and pregnant women was based on their very low omega-3 intake. With intakes at 20-27% of recommended levels, I would consider these groups to be dangerously deficient in omega-3s.

However, the focus on young children and pregnant women was also based on the seriousness of the adverse health outcomes associated with low omega-3 intake in these population groups.

  • According to the authors low intake of EPA and DHA during pregnancy and early childhood is associated with maternal depression, pre-term births, low birth-weight babies, increased risk of allergies and asthma, problems with learning and cognition, and other neurocognitive outcomes.

There is, however, a simple solution. The authors of this study also concluded:

  • “Individuals taking EPA/DHA containing supplements had significantly elevated intake compared to individuals not taking omega-3 fatty acid-containing supplements or not reporting any supplement use.”
  • “As supplement use is associated with increased omega-3 intake, supplementation could be an important source of EPA/DHA, particularly for pregnant women given their lower fish consumption compared to non-pregnant women of childbearing age.”

For more details on the study and my recommendations for omega-3 supplementation, read the article above.

 

These statements have not been evaluated by the Food and Drug Administration. This information is not intended to diagnose, treat, cure or prevent any disease.

Health Tips From The Professor