Vitamin absorption depends on many complex factors, including form and diet. The best form of vitamin supplement for you depends on your health and needs.

Many different types of supplemental vitamins are available today from a range of vitamin brands. They are available as capsules, tablets, liquids, and powders.

Although more research is necessary, various factors may affect nutrient absorption, including dietary fat intake, interactions between foods and vitamins, and even stress.

This article reviews everything you need to know about which vitamin supplements offer the best absorption and how to maximize vitamin absorption.

Vitamin supplements are available in a variety of forms, including gummies, pills, liquids, and powders.

A 2022 study investigated whether liquid supplements absorb more easily than forms like powder or tablets. The study suggests that liquid may absorb more easily, but more studies are necessary to support this claim.

Although the bioavailability — the ability of a nutrient to be absorbed and used by the body — of some nutrients is fairly well understood, research into the uptake, absorption, and bioavailability of other nutrients in humans is still at an early stage.

Some vitamin manufacturers add coatings to pills to enhance flavor or shelf life. A 2019 article on vitamin D supplements found that coatings may affect the dissolution or absorption of a vitamin.

Water-soluble vs. fat-soluble vitamins

In addition to a vitamin’s form, many other factors affect absorption. For example, water-soluble vitamins absorb differently than fat-soluble vitamins, and others are stored in the body.

There are two main types of vitamins: water-soluble (all eight B vitamins and vitamin C) and fat-soluble (vitamins A, D, E, and K).

Water-soluble vitamins dissolve in water and are generally not stored in the body. Excess amounts exit the body through urine.

You would need to consume these vitamins regularly to prevent shortages or deficiencies in the body. However, one exception is vitamin B12, which can be stored in excess in the liver.

Fat-soluble vitamins dissolve in fats, which then travel through the small intestines and are eventually distributed through the bloodstream. Excess amounts of these vitamins are stored in the body’s liver, fatty tissue, and muscles for later use.

According to a 2021 review, other factors that can affect the absorption of nutrients include:

  • interactions with other foods or vitamins
  • dietary fat intake
  • alcohol
  • age

However, the review studied the absorption of food sources of vitamins, not vitamin supplements. More research on the absorption of vitamin supplements could help with understanding which forms absorb more easily than others.

What is bioavailability?

Bioavailability is the degree or rate at which a substance, such as a medication, becomes completely available to its intended biological destination.

In the context of vitamins, bioavailability refers to the amount of vitamins (nutrients) in ingested food that the body absorbs and uses at the cellular level.

Research suggests many complex factors affect the bioavailability of vitamin supplements, including form, binding agents, diet, and health conditions.

A particular vitamin supplement may have a range of bioavailabilities. In addition, the bioavailability for an individual may vary based on factors such as health and diet.

Here are some steps you can take to improve vitamin absorption.

Pair complementary nutrients

Certain nutrients help each other absorb. For example, fat-soluble vitamins absorb better when you consume them with a small amount of healthy fat, such as olive oil, avocado oil, or almond butter.

Additionally, plant-based sources of iron — such as beans, lentils, and nuts — require vitamin C for absorption. Pairing them with vitamin C-rich foods or vitamin C supplements may improve absorption.

Maintain a healthy gut

Your gut plays an important role in the absorption of nutrients from the food you eat. Maintaining a healthy gut may help make sure your body absorbs essential vitamins and minerals.

You can keep your gut healthy by:

  • eating a balanced diet
  • getting regular physical activity or exercise
  • getting enough quality sleep
  • managing stress levels
  • avoiding smoking

You may also want to consider taking probiotics, which may have beneficial effects on gut health. Your doctor can provide more information about the possible benefits of probiotics for you.

Reduce stress

Research suggests chronic stress may increase the body’s metabolic needs as well as the use and excretion of nutrients. This may lead to low micronutrient levels in the body.

Some options to reduce stress include:

  • maintaining a healthy diet
  • getting enough regular exercise or physical activity
  • having good sleep hygiene
  • practicing mediation or deep breathing
  • signing up for mental health counseling

Talk with your doctor about effective ways to reduce stress. They can work with you to develop a stress management plan based on your health and individual needs.

Consider reducing or avoiding alcohol

Alcohol consumption may interfere with the absorption of nutrients, including water-soluble and fat-soluble vitamins. Frequent alcohol use can also lead to malnutrition.

Consider limiting or avoiding alcohol consumption to make sure your body properly absorbs essential nutrients.

The best form of vitamin supplements for you depends on your individual needs. For example, if you have difficulty swallowing capsules or tablets, you may prefer a liquid vitamin.

More research is needed to understand how the body absorbs different vitamin supplements.

Vitamin B12 can be a hard vitamin to absorb. It requires the help of a protein called intrinsic factor for normal absorption. Some people do not have enough of this protein and may need injections or high dose supplements of vitamin B12.

The most bioavailable form of vitamin A is preformed vitamin A, which comes from foods from animal sources, such as meat, fish, and dairy products).

The absorption of preformed vitamin A supplements ranges from 70% to 90%, while the absorption of provitamin A beta carotene ranges from 8.7% to 65%. Provitamin A beta carotene comes from plant products such as green leafy vegetables.

Although researchers are studying the absorption and bioavailability of nutrients, more research is necessary to understand the absorption of vitamin supplements in various forms.

Many online reports claim that certain forms of vitamins absorb more easily than others. But a broad consensus in the scientific community is lacking.

Some research suggests pairing vitamins, maintaining good gut health, and avoiding alcohol to improve absorption of nutrients. However, this research has focused on food sources of vitamins rather than vitamin supplements.

The best form or type of vitamin for you depends on your individual needs and preferences. Most people can get all the nutrients they need by eating a healthy, balanced diet.

If you’re interested in taking vitamin supplements, talk with a doctor about the benefits and risks, as well as a safe dosage.