What is bioavailability?
Bioavailability is the ability of a substance to be absorbed by the body and have an effect.
Are nutrients more bioavailable from raw foods or cooked foods?
Some individuals may be surprised to hear that bioavailability of nutrients can vary depending on whether the food is consumed raw or cooked. Cooking foods helps to initiate the process of breaking down foods. This partial breakdown makes some nutrients easier for the body to absorb, while others may actually be lost by the cooking process. For example when we cook spinach, vitamin C may be partially lost in the cooking process whereas iron may increase in bioavailability.
How can I enhance bioavailability of nutrients from my foods?
Variety in both the foods we eat and the way we cook them can help to maximize our absorption of nutrients. Certain nutrients help enhance the absorption of other nutrients. When vitamin C is consumed with iron rich foods, the vitamin C helps to maximize the absorption of the iron. Fat soluble vitamins A, D, E, and K, require dietary fat to absorb optimal amounts of these nutrients.
Additionally, nutrient absorption may be decreased by certain food substances. Phytates and oxalates found in foods such as leafy vegetables, whole grains, tea, legumes, nuts, and seeds, can decrease the absorption of certain minerals including calcium, iron, zinc, and magnesium.
Does seasonality of produce affect bioavailability of nutrients?
Purchasing in-season produce and local produce can help assure that you are getting the highest amount of nutrients in your foods. In-season produce has been found to have a higher nutritional content and even improved flavor. Local produce will also likely have an improved nutritional content. This is because foods may lose nutrients as they age. If foods are not in-season, an alternative is purchasing frozen or canned versions of the produce. Foods are frozen and canned at peak ripeness and quickly after harvest. This means that nutrients lost with aging may be preserved.
What is the bioavailability of nutrients from supplements?
You may have heard the phrase “food first,” but in a time where nutritional supplements are very popular, this may be confusing. Since many nutrients have improved absorption when consumed with certain food components, nutrients are typically best absorbed from food sources. Some individuals may benefit from supplementation of specific nutrients. For example, a vegetarian diet is very low in vitamin B12. Additionally, individuals with various medical conditions may be lacking in nutrients due to medications or as an effect of the medical condition. It is important to discuss with your healthcare team if you are adding or discontinuing the use of supplements
