Micronutrients are the term for vitamins and minerals due to the small amounts your body needs. Unlike carbohydrates and fats, vitamins are not a direct source of energy, but they are necessary to obtain energy from food. Recent 2020 data revealed that 77% of women reported taking vitamins and supplements. Without getting into the discussion of whether taking vitamins is unnecessary, considering the vast numbers of women taking them, here are ten things that may surprise you to know.
1. Vitamins are better absorbed through food over supplements, with one exception—Folic Acid.
2. Three things lead to nutrient/vitamin loss: heat, oxygen (when you cut open a fruit or vegetable and expose to air), and light. Think of this when you buy pre-cut vegetables or boil and steam them. The vitamin that suffers the heaviest hit in cut fruits and vegetables is vitamin C, although vitamin A and E also suffer.
3. We count on external sources (food) for most vitamins, but there are three exceptions. We make these three on our own: vitamin D from a cholesterol product, gut bacteria produce vitamin K, and Niacin made from the amino acid tryptophan.
4. Interesting fact about Vitamin C. Only humans, nonhuman primates, guinea pigs, bats, and fish cannot make their own vitamin C.
5. Water-soluble (C and B vitamins) vitamin supplements rarely cause toxicity because the body easily excretes them. Vitamin B6 is an important exception. Women take vitamin B6 for premenstrual syndrome symptom relief, and there have been reports of toxicity at high doses. Vitamin B6 toxicity may occur at doses of 200 mg/day or higher and presents with neuropathy symptoms include walking difficulties and hand and foot numbness. Energy drinks like NOS are also reported sources of B6 toxicity.
6. Folic acid supplementation helps prevent neural tube defects. The American College of OB/GYN (ACOG) recommends women take 400 mcg of Folic Acid one month before pregnancy and 600 mcg while pregnant. In 1998 the United States started fortifying breakfast cereals with folic acid for this reason.
7. Vitamin toxicity from food is rare; it’s much more likely with high doses of supplements. There is an exception. Polar bear liver contains toxic amounts of Vitamin A. Eating 1/10th of a gram of polar bear liver covers your recommended daily allowance.
8. For the mineral Magnesium (Mg), absorption of Mg from mineral water is equivalent to the absorption and bioavailability from food or supplements. A low-calorie way to get Mg.
9. Vitamins and minerals are often added to foods, and we call this fortified and enriched. What’s the difference? Fortified foods have nutrients that don’t naturally occur in the food; an example is adding vitamin D to milk. Enriched food means adding back the micronutrients that were lost during processing. Wheat flour is a typical example that contains folic acid, riboflavin, and iron added back after processing.
10. Vitamin supplements are unregulated. The FDA does not require pre-market testing, and manufacturers are not required to demonstrate product safety or effectiveness. Vitamin manufacturers are also not required to show that what they say is on the label is actually in the product.
I am a Clinical Associate Professor of Medicine at the Keck School of Medicine of USC and a board-certified Internal Medicine physician. For 20 years I’ve had an active private practice in general internal medicine currently at The Doctors of USC Beverly Hills. I am lucky to spend part of my time as the attending physician for medical students and residents during their rotations at LAC+USC Medical Center. I’ve been a medical advisor on leading health social networking sites including Dailystrength.org and Sharecare and currently serve as the medical advisor and blogger for GoodRx.com, a prescription drug price comparison website, and GoodRx care powered by Hey Doctor.
My philosophy of care centers around seeing things we can see coming, and nailing them head-on. I appreciate the idea of sharing power and responsibility for the choices one makes for prevention, treatment, and investigation into medical problems. My hope is to write blog posts to empower patients to navigate their own health by laying out the ways that medicine can guide you with strategies to investigate, prevent, and treat some common medical issues, big and small.
I have appeared on The Doctors, Fox Sports West, The Ricki Lake Show, as well as many local news outlets and have been featured in numerous online and print publications. I am a fellow of the American College of Physicians and honored to be named “Top Doctor” in Los Angeles and Pasadena Magazine for years.