Super - Foods

Professor Michael Eskin

Everyone knows that food provides nutrients needed to keep the body in working order. However, since early civilization, certain foods were recognized for their ability to confer additional health benefits such as preventing and treating certain types of diseases. Over 200 years ago, Hippocrates, the ancient Greek physician and one of the outstanding figures in the history of medicine, was the first to recognize the role food played in disease prevention. His popular quote “Let food be thy medicine and let your medicine be your food” has become particularly relevant today as scientists unravel the health benefits offered by many of the foods we eat.

The Jewish physician Rabbi Moses ben Maimon who lived in the 12th century also recognized the importance of diet to health. In addition to his many writings, including his famous Guide to the Perplexed, he wrote a number of books discussing the relation between diet and health. Considerable research conducted over the past two decades has since, identified food rich in nutrients as well as other components or bioactives with proven health benefits. Such foods have been referred to as Superfoods, an unscientific term used for promoting healthier eating - include many grains, oils, fruits and vegetables. Of these, I will briefly discuss oats, olive oil, blueberries, broccoli, garlic, nuts, salmon, tomatoes, soy and tea.

Central to the benefits derived from Superfoods are their antioxidants. These are molecules that quench and neutralize free radicals produced during the normal metabolism of the body. The production of free radicals by the body under oxidation stress is now recognized by medicine as the primary cause of chronic disease such as cancer, heart disease, Alzheimer’s disease, diabetes and depression. The human body is an oxidative machine that oxidizes (‘burns’) carbohydrates and fats to produce energy. During this process many free radicals are produced which are normally rendered harmless by the body. However, when insufficient amounts of antioxidants are produced, which can occur during illness or as one ages, it is important to supplement with external sources of antioxidants. Consequently, providing antioxidants is one of the key features of these Superfoods.

Oats            The first health claim allowed by the Food and Drug Administration (FDA) under their Nutrition Labelling and Education Act (1990) for a specific food was for diets high in oatmeal, oat bran or oat flour. All these diets were associated with a reduction in coronary heart disease. This improvement, due to a reduction in blood-cholesterol levels, was attributed to the presence of high levels of soluble fibre in oat bran. The component responsible was a linear, high molecular weight beta-glucan. The beneficial effect of oat bran was confirmed by its ability to significantly reduce blood cholesterol in hypercholesterolemic subjects; (people with high bad cholesterol).


Olive Oil
            The beneficial effects of olive oil are not only due to the high level of monounsaturated fatty oleic acid but also the presence of polyphenols naturally present in the oil. One of these, hydroxy-tyrosol, accounts for 70-80 percent of the all the phenols in extra virgin oil. It is a potent antioxidant that scavenges free radicals. The lower incidence of cardiovascular disease associated with the Mediterranean diet is attributed to their presence in olive oil. Olive oil polyphenols have also been associated with a lower incidence of cancers.  


Blueberries
            The black, blue and red coloured varieties of blueberries are provided by a range of compounds known as polyphenols which includes flavenoids and anthocyanins. The health benefits of blueberries are attributed mainly to the potent antioxidant properties of these polyphenols. They are responsible for blueberries scoring the highest antioxidant activity compared to 100 other foods examined. Increasing blood- antioxidant status following consumption of blueberries has been associated with decreased risk in atherosclerosis and cancer.

Broccoli            Studies conducted at John’s Hopkins University of School of Medicine identified a group of sulfur containing compounds, sulforaphane glucosinolates, in broccoli sprouts inhibiting strong anti-cancer properties. Broccoli sprouts were found to be 20-50 times richer in these compared to adult cooked broccoli. This discovery led to a patent for developing cancer chemoprotective food products from broccoli.


Garlic
            The pharmacological properties of garlic, such as lipid-lowering effects, are attributed to the presence of sulfur-rich compounds, particularly allicin. Other beneficial effects reported for garlic include reducing the risk of prostate and gastric cancer as well as lowering blood pressure. Epidemiological data also showed an inverse relationship between garlic consumption and cardiovascular disease.


Nuts
            The consumption of nuts has been associated with improved cardiac functions as well as insulin sensitivity. This is due in large part to the low level of saturated fatty acids and the high level of polyunsaturated fatty acids in the oil. Nuts are also good sources of natural antioxidants such as tocopherols (Vitamin E).


Salmon           
Fish oils such as salmon are rich in omega-3 polyunsaturated fatty acids. These include DHA and EPA which are both effective in reducing cholesterol. Other beneficial effects of fish oil are cancer prevention as well as improvement in brain and immune function.


Tomatoes           
Consumption of tomatoes is associated with a reduction in the risk of prostate cancer. The principle component responsible is lycopene, the most abundant cartenoid in tomatoes responsible for the distinctive red colour of the ripe fruit. Lycopene can also cat as an antioxidant and may play a role in the prevention of atherosclerosis and obesity.


Soy           
Soybean products exert a number of health benefits including protection against cardiovascular disease, renal disease, cancers as well as enhancing bone health. The active components in soy, isoflavones, act as phytoestrogens, because of their similarity in structure to estradiol. Soybean oil contains 61% polyunsaturated fatty acids of which 24% are monounsaturated, 534% linoleic acid and 7,2% linolenic acid. As a result, soybean oil is known to prevent cardiovascular disease and play a role in immune response.


Teas           
Tea is one of the most consumed beverages in the world after water. The three major commercial types of tea consumed around the world are Green, Black and Oolong. An accumulated number of population studies suggest consumption of green and black teas have a number of positive health benefits. Such health benefits associated with teas are mainly derived from their polyphenols, particularly flavonoids. Teas are a rich source of these potent antioxidants capable of protecting against the development of cancer and neurodegenerative diseases. The beneficial effect of tea on the cardiovascular system has also been established.

The different foods discussed briefly in this article represent some of the many Superfoods in our diet. In order to enjoy their health benefits requires eating a diet that has variety, which together with regular daily exercise will ensure a healthy lifestyle.

 

Professor Michael Eskin – Associate Dean ,University of Manitoba – Food Biochemist – winner of numerous scientific awards in the area of food science.

see- Daily Exercise