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Many people take vitamins and dietary supplements, sometimes to manage deficiencies. No scientific evidence suggests that the time of day at which a person takes them reduces or enhances their effectiveness. It is most important to take them consistently.
Taking some vitamins at a specific time, however, may reduce the risk of adverse effects. For example, depending on the type of vitamin, taking a supplement alongside a meal can boost how much of it the body absorbs and improve its impact on overall health.
In this article, we explain the ideal circumstances in which to take different types of vitamins.
Different vitamins work in different ways. This means that some have special considerations on how to take them and whether or not people can eat meals alongside them.
Although research has a few recommendations for preventing side effects, science generally does not support any specific recommendations for taking vitamins at particular times.
It is more important that people do not experience any breaks in their daily supplementation of a vitamin, especially if they are taking it to manage a deficiency.
In general, it is better to avoid supplements altogether and get sufficient nutrition from a balanced diet. However, when vitamin supplements are necessary, people should be able to fit them into their schedule easily. Timings for supplementation are mostly flexible.
The sections below discuss different types of vitamins and when might be best to take them.
The human body does not naturally produce or store water-soluble vitamins. People therefore need to consume these vitamins from animal, plant, and sometimes supplemental sources.
Types of water-soluble vitamins include vitamin C and most B vitamins.
Vitamin C is safe to take in recommended amounts at any time of day. It occurs naturally in a variety of plant products, including orange juice, grapefruit, and lemons.
The body does not store vitamin C, so people should take it on a daily basis, ideally in small doses throughout the day.
When to take B vitamins
People tend to take B vitamins to boost energy and reduce stress.
There are eight different types of B vitamins, each of which has a separate function for the body. The types of B vitamins are:
It is generally safe to take several B vitamins at the same time. Some companies also offer vitamin complexes, which are combinations of the daily amount of each B vitamin.
Because of its energy-boosting abilities, the best time of day to take a B vitamin is after waking up. Also, recent research indicates that vitamin B-6 may potentially interfere with sleep and induce vivid dreams. To avoid this adverse effect, people may wish to take them earlier in the day.
Even though B vitamin supplements are safe to consume, it is most beneficial to obtain these nutrients from food sources.
Fat-soluble vitamins are necessary in small doses. However, taking large doses of fat-soluble vitamins can be harmful or toxic to a person’s body.
Cooking food does not get rid of its fat-soluble vitamin content. Usually, a person will get all the fat-soluble vitamins they need from the diet and do not need to supplement them.
Some examples of fat-soluble vitamins include:
Fat-soluble vitamins dissolve in oil. For this reason, people who do need to supplement fat-soluble vitamins should take them alongside meals to enhance absorption.
However, most people who eat a balanced range of nutrients will get enough fat-soluble vitamins through their regular diet.
Likewise, the National Institute of Child Health and Human Development suggest that women take prenatal vitamins daily, particularly folic acid.
Prenatal vitamins that combine folic acid with other nutrients, such as iron or calcium, are also available.
Taking some prenatal vitamins on an empty stomach may cause indigestion and nausea, according to a 2019 review. If a prenatal vitamin increases feelings of nausea, a woman can consider taking the vitamin with a small amount of food.
Even though the review reported that this does not often occur, taking prenatal supplements with food can reduce the risk of feeling nauseated.
There are a wide variety of prenatal vitamins available, and a woman should exercise caution when choosing which to take during pregnancy. Although many are similar, each may contain differing amounts of nutrients and ingredients, and the Food and Drug Administration (FDA) do not regulate supplements.
Before starting to take prenatal vitamins, a woman should talk to her doctor for suggestions and recommendations. It is possible to consume too many vitamins, and this can cause adverse effects for the woman or the fetus.
Importantly, women should not take double doses of prenatal vitamins.
The human body needs both vitamins and minerals to function. As with vitamins, minerals are available over the counter as supplements. There are many claims about the benefits of mineral supplements for health.
Some examples of minerals include:
People should always exercise caution before taking a mineral supplement. They may offer benefits, particularly for those with a nutrient deficiency, but most research into mineral supplements has been observational, and laboratory studies have been inconclusive.
It is also possible to take too much of a mineral, which can have harmful effects.
People should take minerals daily with food. Taking mineral supplements without food might result in side effects, such as an upset stomach.
There is more and more research indicating that taking vitamins has neither a beneficial nor an adverse effect for most people who take them regularly. For example, a 2019 prospective study found no association between taking dietary supplements and a reduced overall risk of mortality.
People should always approach vitamin use with caution, as they may have unintended consequences if a person combines them with prescription or over-the-counter (OTC) medications.
Women should take particular care when choosing supplements to take during pregnancy. For example, according to a 2019 review of literature, high levels of vitamin A can cause congenital irregularities.
However, in the form of beta-carotene, research found no connection between consuming supplements and adverse effects. Folic acid, in particular, can help with the fetus’s development and prevent spina bifida.
Experts suggest that the best method to obtain vitamins is not through supplements at all.
They recommend that people eat a range of nutrient-rich foods, including:
A nutritious, well-rounded diet seems to be the key to good health, rather than a course of vitamin supplements.
That said, a person should take a multivitamin if they have a deficiency, to help complete the diet.
Still, most vitamins offer no known adverse effects for the majority of people. That said, people who regularly take prescription or OTC medication should consult their doctor before taking any vitamin supplements.
People should take care when considering the use of vitamin and mineral supplements.
Caution is necessary because the link between claims of effectiveness and actual benefits may vary greatly. Also, many vitamins and minerals can be harmful if a person takes them in large doses.
Some vitamins may also interact adversely with a person’s regular medications.
There is limited evidence from independent researchers to suggest that vitamin supplements have any significant effects on overall health.
The time of day at which a person takes a supplement will rarely make a difference, except in reducing the risk of some rare adverse effects of specific B vitamins.
If people do need to take vitamins for a deficiency or to support health during pregnancy, they may need to take the supplement alongside food for better absorption.
Before starting to take a vitamin supplement, a person should consult a doctor to make sure that it will be safe. People should always try to get vitamins and nutrients from reputable outlets, particularly those that specialize in whole foods.
Are there any supplements that take effect overnight?
It is always best to obtain a balance of vitamins and minerals from the diet, but when there is a risk of or a true deficiency, a vitamin or mineral supplement may be necessary.
If a doctor has recommended taking a supplement, the best time to take it would be as soon as the person remembers to take it.
Katherine Marengo LDN, R.D. Answers represent the opinions of our medical experts. All content is strictly informational and should not be considered medical advice.