when to take supplements

When to Take Supplements


A common question around supplements is whether there’s an optimal time of day to take them for the most benefit. For instance, certain supplements may be best absorbed when taken with or without other nutrients. To decide the best regimen for you, it’s helpful to understand how to get the most out of certain supplements.

When is the Best Time to Take Supplements?

The best time to take supplements depends on the convenience for you and your daily routine, along with that specific nutrient’s ability to be processed, absorbed and transported to the cells in the body that require the nutrients. Below are some of the most commonly used supplements and tips to maximize their effect on your body and health.

Fat Soluble Vitamins

Fat-soluble vitamins require the presence of dietary fat to optimize absorption in the body. That’s why it’s best to take vitamins A, D, E, or K with a meal that contains some fat. This might include foods like avocado, nuts, seeds, butter, or olive oil.

Water Soluble Vitamins

Water-soluble vitamins include the B vitamins (Biotin, pyridoxine, folate, cobalamin, thiamin, riboflavin, niacin, and pantothenic acid) as well as vitamin C. You may want to prioritize them first thing in the morning as B vitamins have been associated with improved mood. Any excess or unused water-soluble vitamins get excreted from the body daily, therefore they should to be replenished on a regular basis.


Choosing when to take a protein supplement should depend on your reasons for using it. Protein has a filling effect, so if you’re using it for weight loss it is best to choose a low calorie/protein dense supplement to consume between or shortly before meals. This combination will help prevent overeating as well as curb cravings for unhealthy and calorie dense foods. Protein powders can also be used as after workout supplements, which can be helpful in promoting muscle repair and growth.


The best time to take fiber supplements depends on your reason for taking them. For instance, you may want to take a fiber supplement prior to a meal if your goal is to reduce your calorie intake or to lose weight. The reasoning behind this is that fiber creates bulk in your stomach which speeds up the time it takes for you to feel satisfied or “full” and reduces your desire to keep consuming more food and calories. If your goal is to create more regularity to your bowel regimen, taking fiber early in the day will help create a base to keep you regular throughout the day.


Turmeric is best absorbed when taken with fat, so you may want to take these right around meal times. Additionally, the bioactive component in turmeric, called curcumin, requires a compound found in black pepper, called piperine, for optimal absorption. Many turmeric supplements have piperine added for this reason, but you may also want to use black pepper in whatever meal you’re scheduling your supplement around.

Fish Oil

Fish oil can be taken any time of the day, because most research indicates that its benefits are most associated with consistent, longer term use versus timing of the day. However, some people experience acid reflux when taking fish oil supplements. This may be curbed by splitting it into a morning and evening dose, and not taking it right before laying down to sleep.


Iron can cause nausea if taken on an empty stomach, so the best time to take iron supplements are with or right after a meal.

Additionally, iron needs vitamin C for optimal absorption. Meals that contain foods like citrus, tomatoes, strawberries, broccoli, or bell peppers are a good opportunity to schedule your iron supplement around.

Caffeine and dairy products can inhibit iron absorption, so don’t take a supplement with your morning coffee or a milk-rich meal.


Calcium is best split into two doses during the day for optimal absorption. This is because large calcium doses can spike calcium levels in your blood, which are then excreted by your kidneys and unused. One approach could be to take half in the morning and half in the evening.


Magnesium tends to have a calming effect on the body. If you’re sensitive to this, or you want to use these relaxing effects to your advantage while also increasing your magnesium levels, take this supplement in the evening before bed.


The best time to take zinc supplements is whenever it’s most convenient for you. Some people experience nausea when taking zinc, so if this is the case for you, consider taking it with a meal and not on an empty stomach. Additionally, there is some evidence to suggest that zinc may help improve sleep, so you could also consider taking it at night.

Multivitamins and Prenatal Vitamins

Multivitamins contain a variety of vitamins and minerals, all of which have varying absorptive criteria. The best advice for these types of supplements is just to take them regularly. Prenatal vitamins, which have higher doses of iron and other micronutrients, may cause nausea and therefore may be best to take right before bed.

Depending on what supplements you take, you may want to consider some of the factors discussed above to promote optimal absorption or avoid potential side effects.






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Jaime Rangel, RD
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