Cart 0

Bioavailability and Absorption of Dietary Supplements? 

Posted by Greg Kester on

When a food product or supplement package says that it contains, for example, 3 mg of iron, do you know that your body does not actually absorb all 3 mg? The percentage of iron you absorb is dependent upon several factors, including the form of iron (heme versus non-heme), and the amount of calcium, vitamin C and polyphenolic compounds consumed along with the iron-containing product. Likewise, for every nutrient, drug, or other dietary substance, there is a set of factors that influence its absorption and utilization (that is, how the substance is transported and used by your body’s cells). A few of these factors are water solubility, chemical stability, and the action of detoxification enzymes.

​Collectively, these factors determine the substance’s bioavailability, which is the percentage consumed orally that is absorbed in the gastrointestinal tract and transported to the tissue(s) where it is utilized
in its active form.

Why be concerned about bioavailability you ask? Bioavailability is directly related to the therapeutic activity or strength of many phytonutrients, as well as the percentage of essential nutrients actually absorbed and utilized by your body.

Regardless of how often you take dietary supplements, it’s a good idea be familiar with the concept of bioavailability and how specific ingredients added to supplements are intended to improve bioavailability. Let’s discuss.

Bioavailability and Absorption of Dietary Supplements

A major factor affecting the bioavailability of many natural compounds and pharmaceutical drugs is the action of detoxification enzymes. Your body has an elaborate detoxification system in place to neutralize and eliminate harmful toxins, metabolic waste products, and other, possibly harmless or even beneficial, foreign substances as a defense mechanism against potential toxicity and illness. A certain percentage of the active ingredient in a pharmaceutical drug is actually “detoxified” (i.e. metabolized and deactivated) by your body. Likewise, a percentage of certain naturally-occurring compounds like berberine (found in barberry) is chemically modified and eliminated before such compounds can deliver any benefit.

Your body’s detoxification system consists largely of enzymes, a majority of which belong to the cytochrome P450 (CYP450) family. If you were to inhibit the activity of CYP450 enzymes prior to taking certain drugs, a much higher dose of the active drug would enter your cells, which could be dangerous and potentially fatal. This is the reason why people on certain medications are clearly advised to avoid grapefruit and Seville oranges. These fruits contain compounds that inhibit CYP450 enzymes, thereby reducing the rate at which certain drugs are metabolized and deactivated.  

Again, many naturally-occurring compounds with potential health benefits have low bioavailability due to poor water solubility, chemical instability, or other factors. Resveratrol (found in red wine) and curcumin (found in turmeric) are prime examples; they have low water solubility, are poorly absorbed, and are rapidly metabolized by enzymes. Unfortunately, little is known about the health effects of the metabolites (the enzyme-modified form) of these compounds. The question is: How can the bioavailability of the original compounds be increased? The answer: bio-enhancement.


Bio-enhancers are substances that are used to improve the bioavailability of another substance, typically a drug, nutrient, or phytochemical. Pharmaceutical companies use bio-enhancers as a way to reduce manufacturing costs (less of the active ingredient is required per dose because a greater percentage is absorbed and transported to its site of action). Supplement manufacturers also use bio-enhancers, a common one being piperine (found in black pepper). Piperine does improve the bioavailability of certain nutrients and phytochemicals (for example, vitamin A and curcumin) but does so by inhibiting CYP450 enzymes. Taking piperine, your body may absorb a higher percentage of nutrients and other bioactive compounds present in the diet, but at the risk of exposing your body to a greater load of other potentially toxic substances—not an optimal situation.

The Good News

Not all bio-enhancers work by inhibiting CYP450 enzymes. There are other bio-enhancement methods that show promising results for improving bioavailability, like the ones we use at Ubiotic Health. Liposome encapsulation, emulsions, and phospholipid complexes are a few examples of bio-enhancement methods that have shown to improve bioavailability of certain compounds without affecting the body’s detoxification system. Liposome encapsulation methods often use lecithin as the source of lipid, while phospholipid complexes often use phosphatidylcholine. These methods essentially give the nutrient or phytochemical a helpful "chaperone” to guide them through your body's metabolism by detoxification enzymes. As those are bypassed using healthy methods, solubility and absorption are increased. Be aware, however, that just because you see these ingredients on a supplement label does not mean that the manufacturer is using a bio-enhancement method. Ask your local supplement expert or contact the company to find out if this is the case.

Ongoing research is being conducted into bio-enhancement methods to develop safe and effective ways to improve the bioavailability of many phytochemicals that have therapeutic potential. Stay tuned, because bioavailability will likely become more of a hot topic, especially in the supplement industry.

Ubiotic Health's Bioavailability and Absorption

At Ubiotic, not only do we strive to identify the most well-researched ingredients to support your health, we also aim to make them optimally effective and bioavailable. Absorption is one of the major factors affecting bioavailability, and we have formulated our products so that the bioactive ingredients are optimally absorbed. Here's how we truly focus on absorption with Gluc-Support:
  • Lecithin, along with bile salts, promotes the micellization (making soluble) and absorption of lipophilic (fat-soluble) compounds (e.g. curcumin and silymarin) in the small intestine. 
  • Silymarin (one of the major active constituents of milk thistle) has been shown to improve the bioavailability of berberine (the major active constituent of barberry).
  • Ginger has shown broad-spectrum bioenhancing activity (and has specifically shown to improve the bioavailability of curcumin and silymarin). 
  • We use the pure, biologically active form (stereoisomer) of alpha-lipoic acid (the (R) form), as opposed to a racemic mixture (which contains the (R) and (S) forms. Think of it this way: your right hand doesn't fit well into you left glove. Your body requires the (R) "hand" of alpha-lipoic acid, and can't use the (S) "hand," even though they are mirror images of each other. 
  • We use standardized botanical extracts rather than herb powders or extracts with unspecified potency. 


Anand P, Kunnumakkara AB, Newman RA, Aggarwal BB. Bioavailability of Curcumin: Problems and Promises. Molecular Pharmaceutics 2007;4(6):807-818. DOI: 10.1021/mp700113r.

Bonechi C, Martini S, Ciani L, Lamponi S, Rebmann H, Rossi C, Ristori S. Using Liposomes as Carriers for Polyphenolic Compounds: The Case of Trans-Resveratrol. PLoS ONE 7(8): e41438. doi:10.1371/journal.pone.0041438. 

Coimbra M, Isacchi B, van Bloois L, Torano JS, Ket A, Wu X, Broere F, Metselaar JM, Rijcken CJF, Storm G, Schiffelers RM. Improving solubility and chemical stability of natural compounds for medical use by incorporation into liposomes. International Journal of Pharmaceutics 2011;2(20):433-442.

Sunitha M, Srinivas P, Sadanandam. Phytosomes in herbal drug delivery. Journal of Natural Pharmaceuticals 2010;1(1):14-18. doi: 10.4103/2229-5119.73581.

Zhaojie M, Ming Z, Shengan W, Xiaojia B, Hatch GM, Jingkai G, Li C. Amorphous solid dispersion of berberine with absorption enhancer demonstrates a remarkable hypoglycemic effect via improving its bioavailability. International Journal of Pharmaceutics
 2014;467(1-2):50-59. doi:10.1016/j.ijpharm.2014.03.017.

Share this post

← Older Post Newer Post →