Vitamins and dietary supplements are widespread among American adults and children. The challenge is knowing how to optimally consume these supplements to maximize their benefits and minimize risks. Can you take your multivitamin on an empty stomach or should you eat first? What about iron with breakfast? Or calcium with your daily blood pressure medication for convenience?

According to a report by the Centers for Disease Control and Prevention in April 2023, more than half of adults (58.5 percent) and a third of children in the U.S. took a dietary supplement in the previous 30 days. This makes the need for accurate information on how to effectively take these supplements crucial.

Strategic timing can materially influence how well your body absorbs the nutrients from your supplement. Consistency in how and when you take your supplement could help correct deficiencies and improve overall health.

Taking a daily multivitamin at any time of the day is okay, ideally with food. Food can help avoid stomach upsets and enhance the absorption of fat-soluble vitamins in the multivitamin such as A, D, E, and K.

B vitamins and vitamin C are water-soluble vitamins and are fine to take at any time, although B12 is reportedly better taken in the morning. Vitamin C, as it does not stay long in the system, is recommended to be divided and taken in smaller quantities two to three times a day.

Conversely, fat-soluble vitamins such as A, D, E, and K should ideally be taken with a meal or snack containing fat. Optimal absorption of fat-soluble vitamins is facilitated by dietary fats.

Calcium supplements are better with food but in 500-600mg doses or less at a time, for efficient absorption. These can interact with various medications, so consult your doctor if you're on medication.

Iron supplements are typically recommended on an empty stomach for best absorption but can also lead to nausea. Taking it with some vitamin C-rich food or beverage aids absorption and can help manage the queasiness. Be mindful of potential interference with absorption of some medications such as levothyroxine and some antibiotics.

Finally, mineral supplements like magnesium and zinc can interfere with absorption of certain antibiotics, hence the need for careful timing or consultation with your doctor.