Although eating a balanced diet is the best way to ensure adequate nutrition, popping a vitamin supplement is a good way to fill in the gaps. This is especially true for certain populations, such as vegans, who may not be able to get everything they need from a limited diet, and people recovering from an illness or surgery who may not be eating a normal diet. According to registered dietitian Melissa Dorval, when you take your vitamins can be important because some nutrients are better absorbed with food. Talk to your doctor before taking supplements.
Take Vitamins A, E and K With Meals
The fat-soluble vitamins include vitamins A, E, D and K. These vitamins are absorbed through the walls of the small intestine and stored in your body's fatty tissues. The absorption of these vitamins -- except vitamin D -- is greatly improved when they are taken at mealtime with a food that contains a little fat. Take your fat-soluble vitamin A, E or K supplement at lunch with a salad dressed with vinegar and olive oil or at dinner with a piece of fatty fish such as salmon. Deficiency in these vitamins is rare, so only take a supplement if your doctor has suggested it.
Vitamin D Is the Exception
Vitamin D is also a fat-soluble vitamin, but unlike vitamins A, E and K, vitamin D deficiency is common, affecting 30 to 50 percent of the population, according to a paper published in Journal of the American College of Cardiology in December 2008. Therefore, it's crucial to ensure optimal absorption of your supplement if your doctor has advised you take one. But that shouldn't be too difficult, for vitamin D absorption isn't enhanced or inhibited by food, reports Dr. John Cannell, founder of the Vitamin D Council. Cannell says the most important factor is getting enough to get your vitamin D levels up to 50 to 60 ng/ml. So schedule your vitamin D supplement for a time of day when you know you won't forget to take it.
B Vitamins and Vitamin C Don't Require Food
The eight B vitamins and vitamin C are water-soluble, meaning they are not stored in your body and any excess is excreted in your urine. You need to take these every day if your doctor has prescribed them, but they don't need to be taken with a meal. However, taking a big dose of vitamin C can cause stomach upset, which is more likely on an empty stomach. Take it with a meal or split up the amount your doctor has told you to take into no more than 500-milligram doses to minimize gastrointestinal upset, advises Alan R. Gaby, M.D., on the Bottom Line Health website. Gaby also warns against taking B vitamins at night since they can interfere with sleep. If you're taking those with a meal, breakfast or lunch are best.
Multivitamins With a Meal
If you're popping a daily multi, which will generally include all the essential vitamins plus some minerals, including calcium and iron, your best bet is to take it with a meal containing a little fat. You want to make sure vitamins A, E and K are taken with fat, even though it doesn't matter when you take the other vitamins in the pill. Also a big fat multivitamin rich with nutrients taken on an empty stomach can cause stomach upset and nausea for some people.