Forms of Supplements

Today the supplement market offers a variety of products in the form of tablets, capsules, softgels, liquids, chewables and powders. Each has specific applications but there is a lot of confusion about the pros and cons of each of these forms among our customers. 

Absorption is the most frequent concern

Many customers are concerned that tablets do not break down or absorb quickly or completely compared to liquid supplements. Someone found a statement in the Physician's Desk Reference stating that liquid has a 98% absorption rate compared to about 20% from pills. Marketers used this statement to promote more expensive liquid vitamin products. While this whole absorption rate controversy may have been true for dietary supplements a few decades ago, today's technology is very different and quality is an important factor which plays a major role in absorption.

• High-quality supplements usually use so called “inactive” ingredients or “excipients” that only assist in tablet disintegration and absorption, such as tiny cellulose beadlets that expand when they absorb water, helping to break down the tablet within the stomach.  Also, the natural coating on a tablet can facilitate better dissolution. This and other absorption-enhancing features are present in high quality multivitamins, but are generally lacking in the less expensive, lower quality supermarket brands.
• All reputable manufacturers test and re-test their products for acceptable dissolution times and thoroughness under stomach-like conditions according to the US Pharmacopeia.
• Multivitamins designed based on synergistically interacting components usually display better absorption as micronutrients can complement each other in their transit through the gastrointestinal tract and then crossing the endothelium.
• Faster dissolution is not necessarily better.  Many people spend extra money for liquid supplements based on a belief that they will absorb faster than capsules or tablets. They may, but the time difference between complete absorption of liquids versus other forms (20-30 minutes) does not amount to a noticeable advantage or a nutritional advantage with most supplements.  In fact, where higher potencies are concerned, slower absorption may be preferable to fast, sudden absorption. This is because there are limits to how fast and how much of a given nutrient can be absorbed per unit of time. When you overwhelm these absorption pathways, you do waste nutrients.  In general, slower is better when it comes to essential nutrients.  The faster absorption can make a difference only for specific types of supplements such as pre-workout or sports or energy products. Perhaps the idea that faster absorption is better comes from advertisements about medications. This is especially important for pain medication where, in this case, faster definitely is better.  But it is important to avoid applying drug-type standards to supplements. Both types of products are completely different.
• Other factors affecting nutrient absorption include the individual ability to digest a given component. In most cases describing tablets that pass through the body unabsorbed, or statements that “vitamins simply make expensive urine”, there is often a problem with something other than the tablet itself. It may happen in people with an already-weak or poorly-functioning digestive system (such the elderly or convalescents), or in people suffering a digestive illness or food contamination. Both can greatly decrease transit time through the digestive tract, resulting in loose stools and sometimes undissolved tablets.

The importance of biological efficacy testing.

There is no one perfect format in assessing the functionality of a multi-nutrient product and there is a need for more scientific evidence to determine whether one format is more effective than the other and in which aspect.

Ultimately, what matters to every customer is whether a supplement they are taking is effective in addressing specific health concerns. The best test in our opinion is the “efficacy test”. This test allows measuring the various cellular aspects we expect to achieve from taking a supplement, i.e., an increase in antioxidant potential, collagen synthesis support, protection of cellular structures from sugar damage, immune system support, etc. This is why we include such tests as a characteristic of our supplement programs.

Unfortunately, most supplement manufacturers concentrate on the technical and marketing aspects of their products with little attention paid to the efficacy which is the most important aspect. It is not the format in which the vitamins are delivered but rather the quality, quantity and combination of the micronutrients which are delivered that makes the difference.

Different supplement formats

Tablets are the most cost-effective supplements in general which allow the manufacturer to pack the most material into a given space.  Tablets are the most shelf-stable choice and retain their potency over a longer time (2-3 years) compared to liquids, powders and most capsules. Tablets can be offered in a wide range of sizes and shapes.   And as long as you choose product from a reputable manufacturer, formulate it based on nutrient synergy and take it as directed, you do not need to worry about absorption issues with tablets.

Drawbacks:  Large tablets can be hard for some people to swallow (they can be crushed just before use).  Tablets do not offer the flexibility of dosing that liquids and powders do.

Capsules are widely used in supplements because they are easy-to-swallow and break down quickly in the stomach, although not to the point that there is any nutritional advantage.  Vegetarian capsules are a gelatin-free alternative for customers hesitant to consume meat by-products like gelatin.  Some people like that capsules can be opened for the use of all or part of it’s the powdered contents, i.e., mixing the nutrients in applesauce or a protein shake.  That can be an advantage for children or others who have difficulty swallowing pills.

Drawbacks: Capsules cost more than tablets and have significant space and potency limitations since their powdered contents cannot be compressed to a significant degree.  Since capsules are not air-tight, their shelf-life is shorter than tablets.

Softgels are one-piece gelatin capsules almost exclusively used for liquid or oil-based formulas. Although vegetarian softgels have been introduced to the market, adoption has been slow and gelatin softgels are the most common type on the market. Because of their smooth contour and shape, softgels are very easy-to-swallow regardless of size. They also offer superior shelf-life compared to capsules, liquids and powders since they are completely sealed and air-tight. 

Drawback: Softgel manufacturing is specialized and considerably more expensive than tablets or capsules, and therefore softgel products cost more.

Chewables need no explanation. But they always cost more on a dollar-per-milligram basis and tend to be lower potency when compared to comparable products in tablet and capsule forms. They usually have some sugar and flavorings added which many health-conscious people strenuously try to avoid. Chewables are best-reserved for children or those who really can not swallow tablets or capsules.

Powders can be very cost-effective, but they must be mixed in liquid (i.e., water, juice, shakes) or food. Powders do offer great flexibility with dosing – you can make much finer adjustments to the dose than with tablets and capsules.  For supplements taken in gram quantities powders are much more practical.

Liquid supplements. Customers often seek out liquid supplements based on their belief that liquid supplements absorb faster and are therefore better than other forms. This difference is not great enough to amount to a noticeable or significant nutritional difference, so that is not educated reasoning to go liquid.  And, as previously stated, when it comes to essential nutrients, slower absorption may be better. However, liquids offer flexibility with dosing and are very easy for most people, especially children and the elderly, to take.

Drawbacks: Liquid supplements are always more expensive and their shelf life is shorter than with other formats. They are heavier to transport. They are not portable like capsules and tablets. They often require refrigeration. Many contain flavoring and other ingredients that should be avoided. For instance Centrum multivitamin liquid product contains 5 g of sugar per serving in addition to ethyl alcohol, polysorbate 80 (neurotoxin), and synthetic vitamin E (DL form )and other low potency ingredients. It is always important to read labels when buying any product.

Dr. Aleksandra Niedzwiecki

Dr. Rath Research Institute

San Jose, CA, USA