In more recent years, the anti-carcinogenic activity of curcumin both in prevention and treatment has been studied in colon, bone marrow, breast (Liu et al., 2013), prostate, and lung cancer (Sharma et al., 2001; Gomez-Bougie et al., 2015; Tieten et al., 2010; Tsai et al., 2015). While curcumin has been established as safe and nontoxic at high doses in humans (Krishnakumar et al., 2015), how curcumin has such a diverse range of medicinal effects is less understood. The liver is the major organ responsible for metabolizing or breaking down substances. When something is ingested, it is normally absorbed into the
When you swallow any natural health product (NHP) like an herb, vitamin or any other supplement in a capsule, lozenge, or tablet, you expect that the product gets absorbed into the blood andreaches the target site, whether it is a sore knee, an inflamed ankle or a sluggish liver you are trying to invigorate. Bioavailability is a fancy pharmaceutical term that describes how much of an active ingredient is absorbed into the blood by the body and remains unchanged before it reaches its target destination1. It’s a common fallacy to think that just because one is taking a natural product, it will get absorbed into the blood intact. An ingredient with poor or low bioavailability is unable to reach the bloodstream in significant amounts. Either it is not absorbed, or it is broken down and metabolized before reaching target tissues1, rendering it less effective. Bioavailability is a huge problem in the pharmaceutical and natural health world. Unfortunately, it is estimated that over 40% of all new pharmaceutical drugs, even though they may show considerable early promise, are abandoned because of poor bioavailability2. With natural products that have a very diverse chemical structure this can be an even bigger problem. Quercetin, green tea extract, co-Q 10 and especially curcumin (the yellow pigment found in turmeric root and widely used in Asian cuisine) all have poor bioavailability – anywhere from 1-10%3,4,5. Thus, high bioavailability is the ultimate goal for any pharmaceutical or NHP as it promises better efficacy. Bioavailability is dependent on a number of factors, including1:
• Solubility – The active ingredient must dissolve in the stomach. Very little is going to get absorbed if it isn’t soluble (think sand mixed with water).
• Stability – The ingredient must not be destroyed by the contents of the gut. Surviving harsh acidic or alkaline conditions in the gastrointestinal tract is very important.
• Permeability – The active ingredient must be able to permeate, or get across, the cells of the stomach or intestines before it can get into the blood.
• Metabolism – The active ingredient must resist break down by enzymes present in the lining of the gut, and to a greater extent in the liver, where compounds are broken down.
The challenge for any formulation scientist is to overcome these issues. Let us take curcumin, perhaps the most widely studied natural health product on the planet, as an example. Unfortunately, curcumin has one big drawback and that is its poor bioavailability which necessitates very large doses in NHPs (sometimes up to 10 grams)4.If the bioavailability of curcumin could be improved, you would have a natural product that could compete with any pharmaceutical!
There are many strategies for improving bioavailability including: making micelles or liposomes (little fat globules) with phospholipids, reducing particle size to nanometer range, or sublingual delivery through the mucosa (membranes) lining the mouth. This way the ingredient bypasses the liver (where extensive metabolism normally takes place) and thus achieves higher blood levels.
One of the biggest advantages of offering nutrients in a softgel is that it allows better bioavailability of active ingredients than a tablet, capsule or powder5.
While tablets and two-piece rigid capsules are widely used, there are alternative delivery systems including softgels that allow for better delivery of nutrients to the body and thus more effectiveness5.
Tablets and two-piece capsules contain ingredients in the solid state and thus need to first dissolve in the stomach before absorption can begin to take place. Sometimes tablets may not dissolve properly because they are “hard”. Softgels, on the other hand, contain ingredients in liquid form and thus allow for greater absorption of nutrients.
There are some other distinct advantages of softgels over tablets and capsules including:
.• The flexible shapes make softgels easier to swallow, particularly for seniors and children.
• Because softgels are fully sealed they allow sensitive ingredients to be protected from humidity and oxygen, providing better product stability. Some ingredients that have a strong odor or unpleasant taste can be better presented in a softgel, which can better mask odor and taste than a tablet.
• A punctured softgel will leak or become discolored, making it much easier to detect possible tampering or contamination6 – not so with capsules or tablets.
• Customers also usually report reduced stomach discomfort when digesting softgels than when taking tablets or rigid two-piece capsules7.
• Softgels are also ideal for oils and fat-soluble ingredients, e.g. vitamin D, vitamin K or omega-3 etc.
• New vegetarian and vegan softgel encapsulation ensures that people with dietary restrictions have greater freedom in their supplement choices.
• Softgels can be designed in such a way that active ingredients are released in a specific area of the gastrointestinal tract. For example, enteric coatings allow softgels to pass through the harsh stomach environment with its low pH without being broken down, or can even deliver the active nutrient directly to the colon for instance. This delivery system is known as “colonic release” and is gaining strong interest. A good candidate for this type of technology might be curcumin from turmeric, or boswellic acids from the Ayurvedic herb boswellia, which may be better able to address specific health conditions like inflammatory bowel disease (IBD) including Crohn’s disease. Colonic release may also lend itself as an ideal system for delivering probiotics right to the colon where there is the largest concentration of gut microbiota.
• Softgels may also be more resistant to certain environmental conditions e.g. temperature or moisture fluctuations, making them easy to transport and store7.
Softgels are an ideal delivery system providing greater absorption and thus fasterand greater effectiveness.
Besides colonic release, another unique delivery system with regard to softgels are chewable softgels known as “chewals”. Unlike gummies which unfortunately require a lot of excipients (additives such as sugar and gum), chewals offer a distinct advantage of requiring few excipients in small doses, and offer the additional advantage of buccal absorption of ingredients, which allows them to be absorbed straight into the blood, avoiding the liver. An added benefit of this delivery system is that the release of the active ingredients is much quicker, so blood levels rise rapidly ensuring a quick effect, which is useful for pain relief among other things. Another softgel delivery system is the new rapid release of ingredients like ginger. The patented process ensures that the bioactive is rapidly released due to the softgel rapidly disintegrating by use of novel gelatin polymers that dissolve quickly in the stomach. In the case of ginger this would ensure quick relief for nausea. Softgels are a very versatile delivery system that are affordable and can be designed to release active ingredients anywhere in the body from the mouth to the colon.
1. Ranade, V. V. (1991), Drug Delivery Systems 5A. Oral Drug Delivery. The Journal of Clinical Pharmacology, 31: 2–16. doi:10.1002/j.1552-4604.1991.tb01881
2. Melia, C. D. and Davis, S. S. (1989), Review article: mechanisms of drug release from tablets and capsules. I: Disintegration. Alimentary Pharmacology & Therapeutics, 3: 223–232. doi:10.1111/j.1365-2036.1989.tb00208.
3. Johnson, E. J., Vishwanathan, R., Rasmussen, H. M., & Lang, J. C. (2014). Bioavailability of AREDS1 micronutrients from softgel capsules and tablets: a pilot study.Molecular Vision,20, 1228–1242.
4. Siviero A, Gallo E, Maggini V, Gori L, Mugelli A, Firenzuoli F, Vannacci A (2015) Curcumin, a golden spice with a low bioavailability. J Herb Med 5:57–70.
5. Debotton, N. and Dahan, A. (2017), Applications of Polymers as Pharmaceutical Excipients in Solid Oral Dosage Forms. Med. Res. Rev., 37: 52–97. doi:10.1002/med.21403
6. Jackowski, S. A., Alvi, A. Z., Mirajkar, A., Imani, Z., Gamalevych, Y., Shaikh, N. A., & Jackowski, G. (2015). Oxidation levels of North American over-the-countern-3 (omega-3) supplements and the influence of supplement formulation and delivery form on evaluating oxidative safety.Journal of Nutritional Science,4, e30. http ://doi.org /10.1017 /jns .2015.21
7. Lachman L. Physical and chemical stability testing of tablet dosage forms.J Pharm Sci 1965 ;54(10 ):1519–1526