What Nutrients Are Missing In Prenatal Supplements?

Do These Deficiencies Matter?

Author: Dr. Stephen Chaney

healthy pregnancyIf you are a pregnant mom, nothing is more important than the health of your baby. And if you are pregnant or thinking of becoming pregnant, your doctor has probably recommended a prenatal supplement. But does the prenatal supplement he or she recommended provide you with all the nutrients you need?

In a previous issue of “Health Tips From the Professor” I shared two studies that suggested the answer is, “No”. Those studies concluded that most prenatal supplements had little or no vitamin K, choline, DHA, and iodine – all of which are essential for the health of your newborn baby. And while most prenatal supplements contained calcium, the amount they provided was far below recommended levels.

The authors of the first study also made the point that most women going on a prenatal supplement will probably discontinue taking their multivitamin supplement, so a good prenatal supplement should provide all the essential nutrients.

But they don’t. Folic acid, iron, calcium, and vitamin D have long been recognized as essential for a healthy pregnancy. So, virtually every prenatal supplement contained these four nutrients, although calcium is often present in suboptimal amounts. Beyond those four nutrients, the design of prenatal supplements is haphazard. Some contain vitamin K, choline, iodine, or DHA (often in suboptimal amounts). But almost none contain all four nutrients.

And when you consider the other essential nutrients you find in most multivitamins, prenatal supplements often come up empty. Is that a problem? That’s what this study (KM Godfrey et al, PLOS Medicine, 1-27, December 5, 2023) was designed to find out.

How Was This Study Done?

clinical studyThis was a double-blind, placebo-controlled clinical trial, the gold standard for clinical studies. The investigators recruited 1,729 women who were planning to get pregnant from England, Singapore, and New Zealand between 2015 and 2017.

The women were randomly split into two groups:

  • The control group received a supplement containing nutrients that were most frequently included in prenatal supplements in those countries (folic acid, iron, calcium, iodine, and beta-carotene).
  • The intervention group received a supplement containing those nutrients plus riboflavin, vitamin B6, vitamin B12, vitamin D, zinc, inositol, and probiotics).
  • Riboflavin, vitamin B6, vitamin B12, vitamin D, and zinc were included because they are included in most multivitamins but are often missing in prenatal supplements.
  • Inositol was included because some studies have suggested that inositol may reduce the risk of maternal hyperglycemia and gestational diabetes.

Blood samples to assess nutritional status were obtained from all women in the study before the trial started (baseline) and after 1 month of supplementation with either the control or intervention formulation.

Of the women entering the study, 512 went on to have a singleton (one child) pregnancy. For these women supplementation was continued until childbirth. Additional blood samples were obtained in early and late pregnancy and at 6 months postdelivery. [Note: no supplementation was provided to either group postdelivery. And this is also a period of time when most women would be breastfeeding.]

The blood samples were tested for:

  • Blood levels of folic acid, riboflavin, vitamin B6, vitamin B12, and vitamin D.
  • Functional biomarkers of deficiencies of each of these vitamins.

What Nutrients Are Missing In Prenatal Supplements?

Question MarkThere was no difference in maternal hyperglycemia or gestational diabetes between the control group and the intervention group supplemented with inositol, so I will focus on the other nutrients present in the intervention group.

At baseline when subjects were first entered into the study.

  • 29.2% of the subjects had low or marginal status for folic acid.
  • 82.0% of the subjects had low or marginal status for riboflavin.
  • 1.3% of the subjects had low or marginal status for vitamin B6.
  • 9.1% of the subjects had low or marginal status for vitamin B12.
  • 48.7% of the subjects had low or marginal status for vitamin D.
  • 91.0% of the subjects had low or marginal status for one or more of these vitamins.

In the control group receiving folic acid but no riboflavin, vitaminB6, vitamin B12, and vitamin D:

  • Folic acid deficiency fell to 4.1% after 1 month of supplementation (the supplement used by the control group contained folic acid), 1% in early pregnancy, 6.1% in late pregnancy, and rose to 31.8% 6 months after supplementation was discontinued. The intervention group got the same amount of folic acid, and their results were similar.
  • Riboflavin deficiency ranged from 82-92% during pregnancy and returned to 82% 6 months postdelivery.
  • Vitamin B6 deficiency increased to 54% in late pregnancy and returned to 1.2% 6 months postdelivery.
  • Vitamin B12 deficiency increased to 55% in late pregnancy and returned to 12.4% 6 months postdelivery.
  • Vitamin D deficiency ranged from 35-43% during pregnancy and returned to 31% 6 months postdelivery.
  • Functional markers of vitamin B6 deficiency were evident by late pregnancy.

In short, data from the control group fell into 3 categories:

  • The data with folic acid confirm previous studies showing that folic acid in the amount present in most prenatal supplements is effective at preventing folic acid deficiency before and during pregnancy. It also strengthens the argument for continuing folic acid supplementation during breastfeeding.
  • Deficiencies of riboflavin and vitamin D are prevalent in women of childbearing age, but pregnancy does not appear to significantly impact the percentage of women who are deficient in these nutrients.
  • Deficiencies of vitamins B6 and B12 are rare in women of childbearing age, but pregnancy significantly depletes both nutrients.
    • This was particularly evident for vitamin B6. Blood levels of vitamin B6 markers decreased to a level that could impact the functioning of vitamin B6-depended metabolic pathways.

pregnant women taking vitaminsFor the intervention group receiving additional riboflavin, vitamin B6, vitamin B12, and vitamin D:

  • Deficiencies of these vitamins were eliminated by one month of supplementation.
  • Vitamin levels remained adequate during pregnancy.
  • Except for vitamin B12, deficiencies of these vitamins reappeared when supplementation was discontinued for 6 months. The maintenance of adequate B12 levels 6 months after supplementation stopped was expected because the body holds on to its B12 stores very tightly.

In short deficiencies of these nutrients before and during pregnancy could be eliminated by supplementation with levels of these nutrients found in many multivitamins.

The authors concluded, “Over 90% of the trial participants had low concentrations of one or more of folate, riboflavin, vitamin B12, or vitamin D during preconception, and many developed markers of vitamin B6 deficiency in late pregnancy. Preconception/pregnancy supplementation in amounts available in over-the-counter supplements substantially reduces the prevalence of vitamin deficiency and depletion markers before and during pregnancy, with higher maternal plasma vitamin B12 maintained during the recommended lactation period.”

Do These Deficiencies Matter?

New ParentsIt is well established that deficiencies of folic acid and vitamin D cause health risks for the mother and developmental risks for the fetus, so I won’t discuss these nutrients here.

However, the effect of riboflavin, vitamin B6, and vitamin B12 deficiencies on pregnancy is less well known, which is probably why these nutrients are often not added to prenatal supplements.

The authors of the study said small studies have suggested that:

  • Low or deficient riboflavin status may be associated with a higher risk of anemia during pregnancy.
  • Low vitamin B6 status may be associated with an increased risk of preterm birth and development of metabolic health risks in the child.
  • Low vitamin B12 status may be associated with increased risk of gestational diabetes and pre-eclampsia in the mother, and increased risk of neural tube defects, preterm birth, low birth weight, and neurocognitive delays in the baby – with the strongest evidence being an effect on neurocognitive development.

While none of these risks have been definitively proven, the authors point out that deficiencies of these nutrients can easily be eliminated with inexpensive, over-the-counter multivitamin supplements.

What Does This Study Mean For You?

Questioning WomanPerhaps I should start this section by asking why these deficiencies are so common in women of child-bearing age.

The authors speculate that part of the reason is that many women are giving up meat (B12 and iron) and dairy (calcium and riboflavin) for health or environmental reasons.

However, they also point out that a more likely cause is that more than 60% of calories consumed in countries like England, New Zealand, and the United States comes from ultra-processed foods – otherwise known as “empty calories”.

Whatever the cause, the authors conclude, “…the findings suggest a need to reappraise dietary recommendations for preconception and pregnancy to consider further the role of multiple micronutrient supplements for women living in higher-income countries.” I agree.

In a previous “Health Tips From the Professor” article, I reported a recent study showing that most prenatal supplements have either no or inadequate amounts of vitamin K, choline, DHA, iodine, and calcium, nutrients that are absolutely essential for a healthy pregnancy. And I gave recommendations for choosing the best prenatal supplement for you and your child.

That study also noted that many women discontinue their multivitamin supplement when they start taking a prenatal supplement. The current study indicates that practice may be unwise. It shows that:

  • Many women of childbearing age are deficient in one or more of these essential nutrients, and…
  • Essential nutrients not found in most prenatal supplements may also be important for a healthy pregnancy.

So, if you are pregnant or thinking of becoming pregnant, follow this article’s recommendation to start with a well-designed prenatal supplement that provides adequate amounts of folate, iron, calcium, vitamin D, vitamin K, choline, DHA, and iodine and add a multivitamin supplement that provides the other essential nutrients. Alternatively, a simpler approach would be to choose a well-designed prenatal supplement that includes all the essential nutrients. That would be my recommendation.

I would also note this study showed that deficiencies of most of these nutrients reappeared as soon as supplementation was discontinued. Although the authors of this study did not mention it, this reinforces the importance of continuing supplementation during breastfeeding.

The Bottom Line

I have previously reported on a study that concluded many prenatal supplements lack one or more nutrients shown to be important for a healthy pregnancy. But let’s say you have found a prenatal supplement that provides all those nutrients. Is that enough?

Studies show that most women stop taking their multivitamin supplement when they start on a prenatal supplement. But is that a good idea? Are there essential nutrients found in multivitamins, but not in many prenatal supplements that are also important for a healthy pregnancy?

A recent study asked that question in women who were trying to become pregnant. The study found that:

  • Many women of childbearing age are deficient in one or more essential nutrients found in multivitamin supplements but often missing in prenatal supplements, and…
  • Essential nutrients not found in most prenatal supplements may also be important for a healthy pregnancy.

For more details about this study and what it means for you 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.

 ______________________________________________________________________________

My posts and “Health Tips From the Professor” articles carefully avoid claims about any brand of supplement or manufacturer of supplements. However, I am often asked by representatives of supplement companies if they can share them with their customers.

My answer is, “Yes, as long as you share only the article without any additions or alterations. In particular, you should avoid adding any mention of your company or your company’s products. If you were to do that, you could be making what the FTC and FDA consider a “misleading health claim” that could result in legal action against you and the company you represent.

For more detail about FTC regulations for health claims, see this link.

https://www.ftc.gov/business-guidance/resources/health-products-compliance-guidance

 ______________________________________________________________________

About The Author 

Dr. Chaney has a BS in Chemistry from Duke University and a PhD in Biochemistry from UCLA. He is Professor Emeritus from the University of North Carolina where he taught biochemistry and nutrition to medical and dental students for 40 years.  Dr. Chaney won numerous teaching awards at UNC, including the Academy of Educators “Excellence in Teaching Lifetime Achievement Award”. Dr Chaney also ran an active cancer research program at UNC and published over 100 scientific articles and reviews in peer-reviewed scientific journals. In addition, he authored two chapters on nutrition in one of the leading biochemistry text books for medical students.

Since retiring from the University of North Carolina, he has been writing a weekly health blog called “Health Tips From the Professor”. He has also written two best-selling books, “Slaying the Food Myths” and “Slaying the Supplement Myths”. And most recently he has created an online lifestyle change course, “Create Your Personal Health Zone”. For more information visit https://chaneyhealth.com.

For the past 45 years Dr. Chaney and his wife Suzanne have been helping people improve their health holistically through a combination of good diet, exercise, weight control and appropriate supplementation.

Which Vitamins Reduce Breast Cancer Risk?

How Can You Reduce Your Risk Of Breast Cancer?

Author: Dr. Stephen Chaney 

Breast cancer is scary. The good news is that treatment has gotten much better. Breast cancer is no longer a death sentence. But most women would prefer to avoid breast cancer surgery, radiation, and/or chemotherapy if they could.

Could something as simple as supplementation reduce your risk of developing breast cancer? If so, which vitamins should you be taking? Or, put another way, which vitamins reduce breast cancer risk?

If you ask your doctor, they will tell you, “Supplementation is a waste of money. Vitamins don’t reduce your risk of getting cancer.” And they will be correct! That’s because these are the wrong questions.

Let me explain. These are “one size fits all” questions. Studies to answer these questions start with healthy women and asks if vitamin supplementation reduces breast cancer risk for all of them. The answer to that question is, “No”. Multiple studies have confirmed this.

But the truth is more complicated. We should be asking, “Who benefits from vitamin supplementation”, instead of, “Does everyone benefit from supplementation?”Supplementation Perspective

I have summed up this concept with the Venn diagram on the right. Every woman does not need supplementation. But those with poor diet, increased need, genetic predisposition, and/or certain diseases may benefit from supplementation. That is why we should be asking, “Who needs supplementation?”.

Unfortunately, while this concept of individualized treatment has led to dramatic advances for cancer drug development, it has been virtually ignored for studies on supplementation and breast cancer risk.

The current study (H Song et al., Nutrients, 14: 2644, 2022) is an exception. It asks whether obese women who wish to reduce their risk of breast may benefit more from certain micronutrients than women of normal weight.

How Was This Study Done?

Clinical StudyThe data for this analysis came from the KoGES study. This was a study administered by the Korea Agency for Disease Control and Prevention between 2004 and 2016. It was designed to provide a scientific basis for personalized prevention of chronic diseases in the Korean population.

Of the 211,721 participants enrolled in the original KoGES study, this study included data from 41,593 women who:

  • Underwent a health examination at 38 health examination centers upon enrollment between 2004 and 2013 and a follow up health examination between 2012 and 2016. The average follow-up period was 4.9 years.
  • Were cancer-free when they enrolled in the study and developed breast cancer prior to their follow-up health examination.
  • Had reliable diet data.

Dietary intake was based on a food frequency questionnaire administered during their initial health screening. Dietary intake of 15 micronutrients (calcium, phosphorous, iron, potassium, vitamin A, sodium, vitamin B1, vitamin B2, vitamin B6, niacin, folic acid, vitamin C, vitamin E, zinc, and cholesterol) and 4 macronutrients (energy, protein, fat, and carbohydrate) was determined from the food frequency data and compared to the Korean Dietary Reference Intakes (KDRIs). [Note: The Korean DRIs are slightly different than US standards.]

  • The women were then divided into two groups based on whether they consumed more or less than the Korean DRIs for each nutrient.

Which Vitamins Reduce Breast Cancer Risk?

Vitamin SupplementsThere were two major findings from this study.

1) When the investigators grouped all the women in the study together:

    • none of the 15 micronutrients and 4 macronutrients analyzed in this study influenced breast cancer risk.
    • This confirms most previous studies that have been designed as a “one size fits all” study. So, if your doctor was relying on this kind of study, they were technically correct in saying that vitamin supplements don’t appear to reduce breast cancer risk.

2) But when the investigators separated the women by weight, an interesting dichotomy was observed:

    • For obese women (BMI ≥ 25 kg/m2):
      • Vitamin C intake above the recommended Korean DRI (100 mg/day) reduced the risk of breast cancer by 46%.
      • Vitamin B6 intake above the recommended Korean DRI (1.4 mg/day) reduced the risk of breast cancer by 52%.
    • For women of normal weight (BMI < 25 kg/m2) neither vitamin C nor vitamin B6 had any effect on breast cancer risk.

The authors concluded, “In obese women, exceeding the recommended daily intake levels of vitamin C and vitamin B6 was associated with a lower risk of breast cancer. However, other micronutrients were not associated with breast cancer risk in these women.” [Note: Supplement use was not included in the diet survey, so above recommended intake of C and B6 was from foods consumed, not from supplements.]

What Does This Study Mean For You?

Questioning WomanThis study is a perfect example of why we should be asking, “Who benefits from vitamin supplementation”, instead of, “Does everyone benefit from supplementation?”

In terms of the Venn diagram I introduced above, some people consider obesity a disease.

But whether you consider obesity a disease or not, it does increase the need for many nutrients. So, it is conceivable that extra vitamins C and B6 might provide benefits in obese women that are not seen in non-obese women.

This is, of course, a ground-breaking study. It is the first study of its kind and deserves to be followed by other studies to confirm this observation. Ideally, these studies would test whether the same effect is seen in other population groups and determine the optimal dose of vitamin C and B6 to reduce breast cancer risk.

However, I am not optimistic that these studies will be done. It is easy to get funding for the “do vitamin supplements benefit everyone?” studies that confirm the existing prejudice against vitamin supplementation.

It is much harder to obtain funding for “who benefits from vitamin supplementation?” studies that challenge the existing paradigm. But these are the kind of studies that are needed most.

How Can You Reduce Your Risk Of Breast Cancer?

As I said, this is the first study of its kind, so you could consider the results as preliminary. However, assuming it might be true:

  • I do not recommend megadoses of vitamins C and B6. The above average intake of C and B6 in this study came from food alone. And we do not have any dose response studies that might define an optimal dose of C and B6.
  • I do recommend balance. Based on this study, multivitamins should provide enough C and B6 to have a meaningful effect on breast cancer risk. And multivitamins are inexpensive and risk-free.

In addition, there are things you can do that are proven to reduce breast cancer risk. Here is what the American Cancer Society recommends:

  • Get to and stay at a healthy weight.
  • Be physically active and avoid time sitting.
  • Follow a healthy eating plan.
  • It is best not to drink alcohol.
  • Think carefully about using hormone replacement therapy.

I provide more detail about each of these recommendations in a recent article in “Health Tips From the Professor”.

The Bottom Line 

Most doctors will tell you that supplementation does not reduce your risk of breast cancer. And that opinion is backed up by multiple published clinical studies.

But the problem is that these studies are all asking the wrong question. They are asking, “Does supplementation reduce the risk of breast cancer for all women?”. A better question would be, “Which women benefit from supplementation?”

A recent study asked both of those questions. They looked at the effect of 15 micronutrients on breast cancer risk.

  1. When the investigators grouped all the women in the study together:
    • None of the 15 micronutrients influenced breast cancer risk.

2) But when the investigators separated the women by weight, an interesting dichotomy was observed:

    • For obese women (BMI ≥ 25 kg/m2):
      • Vitamin C intake above the recommended intake reduced the risk of breast cancer by 46%.
      • Vitamin B6 intake above the recommended intake reduced the risk of breast cancer by 52%.
    • For women of normal weight (BMI < 25 kg/m2) neither vitamin C nor vitamin B6 had any effect on breast cancer risk.

The authors concluded, “In obese women, exceeding the recommended daily intake levels of vitamin C and vitamin B6 was associated with a lower risk of breast cancer. However, other micronutrients were not associated with breast cancer risk in these women.”

For more information on this study, what it means for you, and proven methods for reducing breast cancer risk 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.

____________________________________________________________________________

My posts and “Health Tips From the Professor” articles carefully avoid claims about any brand of supplement or manufacturer of supplements. However, I am often asked by representatives of supplement companies if they can share them with their customers.

My answer is, “Yes, as long as you share only the article without any additions or alterations. In particular, you should avoid adding any mention of your company or your company’s products. If you were to do that, you could be making what the FTC and FDA consider a “misleading health claim” that could result in legal action against you and the company you represent.

For more detail about FTC regulations for health claims, see this link.

https://www.ftc.gov/business-guidance/resources/health-products-compliance-guidance

 

Health Tips From The Professor