Functional Foods: What are They and What do They Do?

The definition of functional foods has been narrowly defined to mean foods that provide physiological benefits beyond nutritive value.

Bite into a juicy peach, and all your senses come alive. As soon as you take the first bite, you hear the sound of your teeth biting through the skin and the feel its fuzziness on your lips, followed by how it tastes and smells. In the broadest terms, this description would define functional foods. In other words, all foods have a function. However, the definition of functional foods has been narrowly defined to mean foods that provide physiological benefits beyond nutritive value.

Certain foods have been singled out because specific biological compounds in them have been shown to prevent or assist in healing diseases. For example, oatmeal because of its beta-glucans, a soluble fiber, is a functional food because it's been proven to lower LDL cholesterol (aka bad cholesterol).

Food as medicine is not a new concept. “Let food be thy medicine and medicine be thy food,” said the father of western medicine, Hippocrates, 2,500 years ago. However, food as medicine fell out of favor in the West with the burgeoning drug industry that began in the 18th century.

In the East, food as medicine has been part of the culture for centuries. The Chinese have used food for both preventative and for healing diseases. Japan has a designation for foods that have specific health benefits. It’s just in the West that food as medicine seems revolutionary.

There is a broad range of the types of foods that are considered functional. Certain fruits and vegetables are noted for their health benefits because of phytochemicals found in them. Compounds from foods are extracted and added to drinks or other foods to boost their health benefits. For example, omega-3 fatty acids are added to the food of egg-laying chickens so the eggs they produce have omega-3s in them. Lastly, chemical components of food are extracted and made into supplements and other products.

Types of Functional Foods

While there is no one agreed upon definition of functional foods, they have been divided into categories: conventional foods, probiotics, and nutraceuticals.

Conventional foods are whole foods, such as plant-based and animal-based foods. Probiotics are beneficial bacteria and microorganisms. Nutraceuticals are isolated bioactive food compounds that have been concentrated and made into supplements, and medical foods.

Conventional Functional Foods

There are a variety of plant and animals foods that are functional foods. Below is a list of the top functional foods.

Salmon and other fatty fish are high in omega-3s. Omega-3s are beneficial for reducing heart disease and cholesterol.

Soy has phytochemicals that reduce cholesterol. Choose whole soy foods, such as edamame, tempeh, and miso.

Tomatoes contain lycopene. Evidence shows lycopene is influential in reducing tumor growth and reducing the risk of cancer. Lutein also found in tomatoes helps with macular degeneration. Cooked tomatoes, such as tomato sauce, release more of the nutrients.

Walnuts are rich in healthy fats, omega-3s, and Vitamin E. Amino acids in walnuts help to reduce the risks of coronary heart disease.

Dark green leafy vegetables are high in phytochemicals that help to protect cells from cancer. They are also good for heart health.

Red wine and grape juice contain resveratrol, which is known to prevent heart disease. For maximum benefit, drink grape juice that has not been mixed with other juices.


Probiotic functional foods are foods with friendly bacteria. They help to treat diarrhea and improve immune functions. They also assist digestion and bowel functions. Yogurt with live cultures, fermented drinks, such as kombucha, and pickled vegetables contain probiotics.


Nutraceuticals are sometimes used interchangeably with functional food. However, Nutraceuticals are an end product created from food compounds and therefore they are a classification of functional foods. There are many products that fall into this category.

Some of them are vitamins made from whole foods. Herbs, such as turmeric and garlic, are put into capsule form for ease of use. Pea protein is an example of an isolated biological compound that is made into a powdered energy shake.

Functional foods need to be part of a healthy diet.

There is a wide body of foods considered functional, each having specific health benefits. Because of this, it is best to consult a professional healthcare provider to help guide you.


Attard, Manuel. Lycopene Benefits (October 03, 2017). Retrieved from
Hasler, Clare. Functional Foods: Benefits, Concerns, and Challenges–A Position Paper from the American Council on Science and Health. Retrieved from
Ross, Sharon. Functional foods: the Food and Drug Administration perspective (June 1, 2000). Retrieved from
Yao, Chunyan, Hao, Ruiwen, et al. Functional Foods Based on Traditional Chinese Medicine (February 23, 2012). Retrieved from

Leave a comment

This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.