What does bioavailability mean? Simply put, it's how nutrients are absorbed by the body. Nutrients that are bioavailable are easy for your body to utilize.
Why do we care about it? Todd Runestad, ingredients and supplements editor, New Hope Network, and advisor to Tespo puts it simply: “Bioavailability is the amount of an ingredient circulating in your blood. If an ingredient doesn’t get absorbed or metabolized, it won’t help your health.”
So what determines how the body absorbs ingredients? A lot. Macronutrients, such as carbohydrates, proteins and fats are usually easy for your body to absorb. We absorb an estimated 90% of the nutrients available from macronutrients. Cooking food, chewing it, digestive enzymes and the overall digestion process all help make macronutrients bioavailable to the body.
But when it comes to micronutrients, such as vitamins and minerals, flavonoids or carotenoids, it’s a different story. These exist in a different form in food that makes how we absorb and utilize them not so predictable. Some micronutrients, such as folic acid, are even more bioavailable to the body in a fortified food or vitamin format than they are naturally in food.
There are also internal and external factors that affect how bioavailable nutrients are to us. Your gender and health status, including pregnancy, are internal factors, as is your age and the aging process. As you age, your metabolism tends to slow down and the digestive system doesn’t work quite as well. With age, you can suddenly have a hard time absorbing nutrients and vitamins that were once very bioavailable to your body.
This tends to be the case with vitamins. Vitamin pills are not only harder to swallow with age, they become more difficult for the digestive system to break down and absorb. When it comes to taking vitamins, you can pop all the pills you want, but if the ingredients aren’t bioavailable to your body, then you’re wasting both time and money. For this reason, liquid vitamins tend to be a better option. They are simply more bioavailable.
This plays into the external factors that affect absorption, which include the form in which you ingest nutrients. Whether a nutrient comes in the form of a food, a pill or a liquid, or if it contains chemicals or artificial ingredients all affect absorption. As Runestad explains, “There was a drug study that compared the bioavailability of tablets versus liquids, and the tablet (pill) was only 50 percent that of the liquid. The researchers thought it was due to slow dissolution of the tablet. Liquid delivery formats give you more nutrition, more pure nutrition and faster nutrition."
Other absorption considerations include the size of nutrient molecules. As well, whether nutrients are fat-soluble (vitamins A, D, E or K) or water-soluble, which are easily excreted (vitamins B and C). Carotenoids, for instance are fat-soluble. Ingesting carotenoids with fats or oils makes them more bioavailable to the body. Many vitamin tablets and pills also contain extra fillers, binders and artificial ingredients. These ingredients make it harder for the body to access the nutrients these pills contain.
“With some large molecules that are difficult to absorb, like coQ10 and curcumin, bioavailability really matters,” says Runestad. “Lots of innovative companies have developed solutions to increase nutrient bioavailability, such as fats like liposomes or technologies like nanoparticles. With supplements, tablets are pressed together and do not always dissolve like capsules. Even capsules have non-nutritive fillers called excipients. Liquids have no such concern. Absorption is immediate. No excipients are needed to maintain pill integrity. It’s a pure nutrient play.”
Although liquid vitamins are more bioavailable to the body, liquid formulas can also contain artificial dyes, sweeteners and ingredients that can limit absorption. That’s why it’s important to look at the quality of ingredients in a product. At Tespo, we focus on high quality ingredients, no filler, binders or artificial ingredients—liquid formulas that contain only what your body needs.