As with medications, always follow package instructions when it comes to taking vitamins. However, while many supplement labels tell you whether to take vitamins on an empty stomach, few let you know which time of day is best. Knowing a few general rules can help make things a bit more clear.
Best Time to Take Vitamins
The best time to take your vitamin, mineral, or multivitamin supplement really depends on what you're taking. For many vitamins, it's best to take them at mealtime to prevent potential unpleasant side effects. Below are a few general rules when it comes to taking different nutritional supplements.
Calcium and Magnesium
Calcium and magnesium supplements are generally taken in large dosages (compared with other vitamin and mineral supplements). Because of this, Consumerlabs.com suggests taking calcium and magnesium supplements at different times of the day than other nutrient supplements to avoid poor absorption from lower-dosage vitamins and minerals (that have to compete with calcium/magnesium absorption). For example, calcium in large amounts inhibits iron absorption.
There isn't a general guideline as to what time of day you should take calcium or magnesium supplements. Registered Dietitian Melissa Dorval R.D., In a Q&A at West Bay Pharmacy, suggests taking calcium supplements with dinner or before bed (but at a different time than other vitamins and minerals). Calcium and magnesium in multivitamin supplements are usually present in smaller amounts, so they shouldn't cause problems with absorption.
Iron Supplements
Iron supplement label instructions generally suggest taking iron with food to help avoid unpleasant side effects (such as nausea and gastrointestinal distress). Avoid taking iron supplements at the same time as calcium supplements to maximize absorption. Vitamin C enhances iron absorption, so take your iron supplement with a vitamin C supplement (or vitamin C-rich food) at lunch or dinner time.
Multivitamins, Vitamin C, and B Complex (Water Soluble Vitamins)
Take your multivitamin, vitamin C supplement, or vitamin B complex vitamins with breakfast or lunch, suggests Dorval. That's because B vitamins enhance your body's metabolism, converting food to energy to get your day started off right. If you're taking an iron supplement, take vitamin C with it during breakfast, lunch, or dinner.
Vitamins A, D, E, and K (Fat Soluble Vitamins)
Fat soluble vitamins are best absorbed when taken with a meal high in dietary fat (such as dinner). Consumerlabs.com recommends taking vitamins A, D, E and K with dinner or another meal or snack rich in healthy fats such as oils, fatty fish, nuts, seeds, nut butters, avocados, or olives.
SAMe
A nutrient supplement some people take to help treat depression and osteoarthritis is called SAMe, which stands for S-adenosyl-L-methioninem. Your body makes this compound to maintain cell membranes and produce and regulate hormones. Consumerlabs.com says taking SAMe with food may reduce potential unpleasant side effects (such as nausea), but the time of day you take it doesn't appear to be as important.
Does a Vitamin's Form Matter?
Vitamin supplements come in all shapes, sizes, and consistencies (such as gummies, tablets, chewables, capsules, and liquids). The form of vitamin you choose doesn't affect the time of day you should take it. Consuming vitamins with meals (spaced out from each other if need be) is what counts most. DaVinci Laboratories says liquid vitamins are absorbed quicker, however.
Take Away Message
The bottom line when it comes to taking vitamin supplements is fairly simple. If you choose a multivitamin supplement, consume it with the meal you're most likely to remember it at. For many people, this means taking vitamins with breakfast or dinner. Consume fat-soluble vitamins with higher-fat meals (such as dinner) and avoid taking large dosage vitamins (such as calcium and magnesium) at the same time as other nutrient supplements to maximize absorption.