When shopping for supplements, it is not unusual to see a label on the front claiming the vitamins are “naturally sourced” or “all natural.” In general, we are attracted to supplements that claim to be natural over their synthetic counterparts. The reasons are many, but there are two main lines of thought.
The first reason has to do with the wide availability of information regarding the negative effects of laboratory-made preservatives and additives, and a subsequent mistrust of ingredients that aren’t easily pronounced. Some of these claims are supported, while others are pure assumptions. The second reason has to do with the belief that things of nature are wholly “good” and cannot damage our health.
Let us first understand what makes “natural” nutrients natural.
What is the difference between natural and synthetic nutrients?
Usually, the FDA has strict guidelines regarding packaging and labeling of food and drugs. Unfortunately, the FDA isn’t much help in this case, as they have not yet developed a definition for the term "natural." This is because the word natural connotes the image of a food in its original form. When we talk about natural nutrients out of the context of the food they come from, they have gone through some sort of process, or manipulation by humans, and are “no longer the product of this earth.”
A petition has been made to the FDA requesting the term “natural” no longer be used on food labels. In the view of some, the only foods that can be called natural are completely unaltered.
For the purpose of continuing to analyze this common question, let us define “natural” and “synthetic” nutrients in the way most of the public understands them:
Natural nutrients are those that are derived directly from plants and animals, like fish and algae oil, and supplements made from whole foods.
Synthetic nutrients are those that are created in the laboratory to mimic the same function and chemical structure as those created in the human body.
Are they absorbed differently by the body?
Some of the factors that affect nutrient absorption (or nutrient bioavailability) are:
Interaction between the nutrient and the environment in which it is found. For example, carrots are high in carotenoids, a powerful antioxidant, but when they are eaten raw, we cannot absorb all of the carotenoids. Cooking them allows our body to extract a much greater amount.
Often, there are different forms of nutrients, some of which are absorbed better by the body than others. For example, there are two types of dietary iron. Heme iron is found mainly in animal products and is a type of dietary iron that is better to absorb. Non-heme iron is found in vegetable products and is more difficult to absorb.
Nutrients that block absorption, iron and calcium for example, compete for absorption within the cell.
Nutrients that need to be consumed together, for example optimum absorption of iron, occurs when consumed with Vitamin C.
In most cases, the chemistry behind the nutrients is no different whether you are talking about a synthetic nutrient or a naturally-occurring nutrient. The main difference arises when examining the environment in which the nutrient is found. If the complementing nutrients are added together in the synthetic supplement, they could technically have the same effects on the body.
The bottom line
While scientists have identified many of these mechanisms and interactions, there is still plenty that we don’t know about food. There may be hundreds or thousands of components within foods that we are not yet familiar with. For this reason, supplements, whether synthetic or natural, will never replace food. Food — especially fresh food — is packed with dozens of vitamins and minerals in adequate proportions that help to contribute to our long-term health.