What is vitamin absorption and why it is important?
When we take a vitamin or mineral supplement whether as a tablet, capsule or powder, our body absorbs the nutrients in the same way – through the wall of the small intestine and into the bloodstream to be taken wherever they are needed in the body. But, how much of a supplement is absorbed, and therefore how effective it will be, depends on a variety of factors. Age, digestive system integrity and your overall state of health can play a part. Absorption can also be affected by nutrients working with or against each other and the quality or form of the nutrient taken. Even the time you take your supplements (i.e., On an empty stomach or after a meal) can have an impact on how well they are absorbed.
How the body stores vitamins and mineralsVitamins are generally classified as either water-soluble or fat-soluble.
Water soluble vitamins, including B vitamins and vitamin C, are generally not stored in the body for long periods of time. The body usually takes what it needs and then the kidneys remove the excess out of the body through your urine. These vitamins need to be replenished regularly through the diet or via supplementation. This is with the exception of vitamin B12 as the body stores B12 reserves in the liver.[i]
Fat-soluble vitamins, such as vitamin A, vitamin D, vitamin E and vitamin K, are absorbed, used throughout the body and then stored in the liver and fat tissues. When additional amounts of these nutrients are required, the body will release what it needs from its reserves back into the bloodstream.
Minerals are stored in many different tissues in the body. For example, almost all (98%) of the body’s calcium is stored in your bones, where it acts as a reservoir. The remaining is found in blood, muscle and other tissues.[ii] More than half of your magnesium stores are in your bones and the rest in various tissues around the body
Is bioavailability and absorption the same thing
Bioavailability is a term that refers to how fast and efficiently a nutrient is absorbed and made available to the body. There are forms of vitamins and minerals that have superior bioavailability and may have an influence on the results you’re hoping to achieve.
Many Ethical Nutrients products feature ingredients with high bioavailability. For example, MetaMag® (magnesium disglycinate), has been shown to be significantly better absorbed when compared to other common forms of magnesium including magnesium oxide and magnesium citrate.[i],[ii] Meta Zn® (zinc diglycinate) and Meta Fe® (iron diglycinate) have also been shown to be highly bioavailable and well-tolerated compared to other forms on the market.
What about “activated” vitamins
Many vitamins such as folic acid, vitamin B6 and vitamin B12, need to be converted into their active form before they can be used by the body for several important functions. Some individuals have trouble with this conversion process. Activated vitamins are already in their “active” or ready to use form, so they essentially bypass a few steps and can be quickly used by the body. Many Ethical Nutrients products contain activated vitamin versions.
Tips to optimise vitamin absorption from your supplements
To get the most out of your supplements, there are a number of things to keep in mind:
- Caffeine can interfere with the absorption of several nutrients including calcium, iron, magnesium supplements and B vitamins,[i] so it is best to take your supplements a couple of hours before or after tea and coffee consumption.
- Vitamin C facilitates the absorption of iron, so make sure your iron supplement contains ascorbic acid or take with a glass of orange juice.
- Calcium can inhibit iron absorption, so where possible it might be best to separate these supplements. For example, taking iron in the morning and calcium at night.
- Consuming a little fat with your fat-soluble vitamins (vitamin A, D, E and K) can help with their absorption. For example, if you’re taking a vitamin D3 supplement, try to consume with a meal that includes avocado, butter, cheese, fish, eggs, olive oil, nuts or nut butter.
- Look for supplements with highly bioavailable ingredients like Meta Mag® for a magnesium supplement and activated forms of B vitamins to support absorption and enhance their health effects.
- Follow the label – some supplements might need to be taken on an empty stomach; others should be taken with food. Some might need to be taken morning and night. This will help optimise absorption and reduce stomach discomfort.
If my body doesn’t absorb the vitamins, will I just urinate the goodness away?
Many people report neon yellow urine after taking certain supplements and might be concerned that their body isn’t absorbing any of the goodness. However, this is the body’s clever way of moderating what it needs and what it doesn’t. The yellow colour actually comes from one particular B vitamin known as B2 or riboflavin. Remember, B vitamins are water-soluble and not stored in the body, which means any excess will be removed through the urine.
References[i] Ankar A, Kumar A. Vitamin B12 Deficiency. [Updated 2021 Jun 7]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2022 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK441923/
[ii] NIH, June 2022, Calcium: Fact sheet for health professionals, Accessed 22/07/2022, URL: https://ods.od.nih.gov/factsheets/Calcium-HealthProfessional/
[iii] Graff D. Bioavailability of magnesium chelazome®Albion® Research Notes. 2000 Mar;9(1):2-3.
[iv] Hartle JW, Morgan S, Poulsen T. Development of a model for in-vitro comparative absorption of magnesium from five magnesium sources commonly used as dietary supplements. FASEB Journal. 2016 Apr;128(6)
[v] Wolde, T. Effects of caffeine on health and nutrition: a review. Food Science and Quality Management. 2014;30:59-65