Health effects of berries

Vitamins C and E

Berries and energy

Phenolic compounds

Vitamin C is the best-known antioxidant in berries. It protects the body against harmful oxidation. Vitamin C also contributes to the formation of bones and teeth. In addition, vitamin C is essential for the formation of collagen, the main component of connective tissue. Vitamin C also boosts vitamin E´s antioxidant effects.

Rose hip, sea buckthorn berry, blackcurrant, cloudberry and rowanberry are all high in vitamin C. No imported fruit has the same levels of vitamin C as these berries. The National Nutrition Council of Finland recommends a daily intake of 75 milligrams of vitamin C for adult people.

Vitamin E serves as an antioxidant, protecting the body against harmful oxidation. It maintains the structure of the cell membrane and protects vitamin A in the body. Vitamin E is a generic name for several vitamin E compounds. Berries have higher contents of vitamin E than fruits. The recommended daily intake is 8 milligrams for women and 10 milligrams for men.

The energy content of food products varies greatly. Generally, vegetables have lower energy content than animal products. Berries have high water content: 80-90% of their total weight. Carbohydrates and organic acids constitute most of the dry components. Berries are low in proteins and fats. Because of their high water and low fat content, berries produce only a little energy. Most of this energy comes from sugars.

Unabsorbable carbohydrates are called dietary fiber. Although the body cannot break down this fiber into an absorbable form, it has many important functions in the digestive tract. Unabsorbable fiber (insoluble) maintains intestinal functions and promotes beneficial bacteria growth. Absorbable (soluble) fiber slows the blood sugar rising after a meal and emptying of the stomach, for example.

Berries contain both insoluble fiber and soluble fiber, pectin. In addition to oat and vegetables, berries are the most important dietary sources of soluble fiber.. Slightly raw and recently ripened berries have the highest pectin content. Berries contain ca. 3-6 % dietary fiber (of fresh weight). It is recommended to get 25-35 g fiber daily.

Plants produce thousands of phenolic compounds. These compounds can have beneficial effects on our vital functions, health and well-being. The most important phenolic compound groups in berries are flavonoids, phenolic acids, lignans, stillbenes and phenolic polymers (tannins).

Flavonoids are metabolic products that function as part of the defence system of plants. In the human body, they serve as antioxidants. Flavonoids and other antioxidants, such as vitamins C and E, can protect the body against the harmful effects of oxygen and the related illnesses. Flavonoids have also been proven to have many other beneficial effects on the health and functions of the body. The most common sources of flavonoids are vegetables, fruit, berries, tea and red wine. Their flavonoid contents vary by the year, depending on such factors as environmental conditions. Most of the flavonoids in berries are anthocyanins. Anthocyanin contents are particularly high in strongly coloured berries, such as bilberries, crowberries, aronia and blackcurrants. Anthocyanins give berries their red or blue-black colour. According to research, berries are the best dietary source of anthocyanins in Finnish diet.

Proanthocyanins are group of phenolic tannin compounds. Their phenolic structure enables them to serve as antioxidants. Especially the properties of short- chain proanthocyanidins have been examined. Lingonberry contains these compounds at least as much as cranberry.

Antioxidants´ total effect in the body is affected by many different compounds, so the amount of single compounds is not so relevant as the total amount of different compounds. One indicator for total antioxidant effectiveness is ORAC value (Oxygen Radical Absorbance Capacity), which tells the total antioxidant potential of a single food. By comparing ORAC values of different foods, it can be easily seen which of them is best in terms of antioxidant capacity. ORAC value is a better indicator for overall healthiness than a single compound.