Many people turn to supplements to meet their nutritional needs—according to the Council for Responsible Nutrition USA, 77 percent of U.S. adults take dietary supplements. While this can be a good thing, it’s crucial to understand if you really need them and to know how they work. The concept of bioavailability, in particular, should inform your decisions regarding supplements.
Bioavailability and Dietary Supplements
Bioavailability refers to the extent and rate at which a drug is absorbed into your bloodstream according to its dosage. When you buy a supplement, bioavailability plays a crucial role in determining whether or not it will “work” for you. While you may think all supplements are equal, and anyone who takes them will experience the same effects, numerous factors influence absorption rates. For example:
- Age
- Gender
- The time of day you take the supplement
- If you take the supplement on a full or empty stomach
- The health of your digestive system
- Your overall health
- If you have a deficiency in the vitamin or mineral you’re supplementing
Assessing the Absorption of Common Supplements
Aside from the factors listed above, different nutrients have varying levels of bioavailability. If you’re looking to supplement your diet to get all the necessary vitamins and minerals, you may want to consider bioavailability as a factor. For some nutrients, it may not be worth taking supplements, and you’d be better off changing your diet to meet your dietary needs.
Here is a list of commonly-used supplements and how the body breaks them down and absorbs them into the bloodstream.
- Vitamin C– Your body does not create vitamin C on its own, so it is essential to get adequate amounts through your diet. According to the National Institutes of Health, “Approximately 70 percent to 90 percent of vitamin C is absorbed at moderate intakes of 30 to 180 milligrams per day. However, at doses above one gram per day, absorption falls to less than 50 percent and absorbed, unmetabolized ascorbic acid is excreted in the urine.” If you consume three grams or more of vitamin C in a day, it can have adverse effects.
- Calcium– The small intestine stores and sends calcium to your bones and tissues after being transported through the blood. However, the extent of absorption depends on the amount of calcium already available in the blood. Also, you shouldn’t take more than 500 milligrams a day to avoid the possible risk of heart disease and kidney stones associated with over-supplementing calcium intake.
- Fish Oil– After fish oil is broken down, omega-3 fatty acids lower the body’s production of triglycerides and use it to lower bad cholesterol in the body. Natural fish oil should be consumed with meals and with possible fat sources to improve absorption.
- Magnesium– Magnesium is absorbed by the small and large intestine and stored in bone minerals. If you consume large doses of it, it is excreted in your urine or feces. To improve magnesium absorption, you should treat vitamin D deficiencies. Click here to learn more about magnesium and check the recommended daily amount for your age group.
- Whey Protein– Whey protein provides amino acids transported through the intestinal wall and passes through the bloodstream for absorption. To improve your absorption, you can consume more probiotics, improving your gut health.
- Collagen Powder– Hydrolyzed collagen powder, also known as collagen peptides, is easily digested because the hydrolysis process breaks the protein down into small particles. To improve collagen absorption, eat food rich in vitamin C. You can click here to learn more about hydrolyzed collagen supplements.
Supplement Savvy
Not everyone needs to take supplements to support their diet, and many supplements on the market far surpass the necessary daily doses of vitamins and minerals. To be a savvier supplement consumer, do your research before hitting the store and make sure you understand supplement bioavailability. You may also want to talk to your doctor about which nutrients you lack and would benefit from taking in supplement form.
