If a pill a day could keep the doctor away, that pill would be a multivitamin. Designed to fill the nutritional gaps in the average diet, the modern multivitamin has progressed way beyond the "alphabet" vitamins to include herbal antioxidants and energy support. Unfortunately, the more ingredients are thrown together into a single formula, the higher the chance of side effects, such as nausea and anxiety. There are ways around the issue; you simply have to find the formula that works for your particular lifestyle.
Wrong Vitamin Balance
Most people take multivitamins to make sure they get all the nutrients their diet may not provide. As such, many multivitamins provide the total recommended daily intake of each vitamin, or close to it. Most vitamins and minerals are harmless if you get more than you need, and the extra just gets excreted. But others, like phosphorus, iron, zinc and selenium can cause nausea and other gastrointestinal issues at high doses. So if your usual diet already provides enough of these nutrients, dosing yourself with more every morning is almost sure to lead to problems. Speak to your doctor or a nutritionist to find out what vitamins you actually need to supplement based on your diet.
Fillers
Your multivitamin is more than just vitamins; it also contains fillers and binders that allow the manufacturer to mold it into a pill shape that won't crumble or degrade easily. The additives in the multivitamins can be harsh on an empty stomach and easily lead to nausea, so take your vitamin with food or shortly after eating to avoid this problem. The problem is that some vitamins, such as B-12, are better taken on an empty stomach, so consider taking a separate B-complex in liquid-capsule form, which is less likely to cause stomach upset, or choose a liquid multivitamin that is free of additives.
Drug Interactions
Some medications may interact negatively with multivitamins, and your doctor may recommend separating your dose of each by a few hours. For example, a 2010 study in the "American Journal of Therapeutics" found that a commercial vitamin supplement caused nausea and vomiting in women taking birth control pills or hormone replacement therapy after changing the formula to include a certain antioxidant. Further investigation showed that this antioxidant reduced the rate at which estrogen was eliminated from the body, resulting in estrogen levels high enough to cause unwelcome side effects. Consult your doctor before taking multivitamins if you are taking any medication or supplement.
Stimulant Blends
While nausea is a common multivitamin side effect, anxiety is not. In fact, anxiety is a symptom of several vitamin deficiencies, so your multivitamin should actually help ease your stress. The exception is multivitamin formulations that contain stimulants. These are marketed as "energy" or "enhanced metabolism" blends and are normally marketed to consumers as weight-loss drugs. These formulas contain caffeine or herbal stimulants, such as guarana or yerba mate, and can cause nervousness and anxiety in sensitive people. Choose a different multivitamin and read the label to make sure it is stimulant-free.
References
- MedlinePlus: Multivitamins
- "American Journal of Therapeutics"; Vomiting From Multivitamins: A Potential Drug Interaction; F. Greenway F, et al.; May 2010
- "Canadian Medical Association Journal"; Too Much of a Good Thing?/ Toxic Effects of Vitamin and Mineral Supplements; Eric Wooltorton; July 2003
- DrDonnica.com; Multivitamins and Nausea; Donnica Moore; October 2006
