Currently, there is an upsurge of interest in functional components of food ingredients. This is mainly due to the fact that many studies have shown that the reactive oxygen species (ROS) including oxygen free radicals that are formed under stressful conditions and ageing are part of the etiology of degenerative disorders.

Many researchers have shown that  ROS are responsible for the modification  and  damage  of proteins, carbohydrates, and DNA which in turn leads to several type of  cancers. Free radicals attack unsaturated fatty  acids of biomembrane, which results in lipid peroxidation as well as desaturation of proteins and DNA.

"Flaxseed"  popularly known as  Linseed (Linum usitatissimum)  is an  important oilseed crop grown around the world for its oil and fiber. Flaxseed is an important commercial oilseed crop  grown in India. Some of the varieties being grown in India are Mukta, Hira, Jawahara1, 7 and 17, Himalini, Sweta, Jeevan, S-36, K-2,  LCK-152, Neelum, LC-54, Chambal etc. The different parts of the flaxseed plant is commercially important. The seed is processed for its oil while  stalk is for fibre.

Flaxseed has been consumed as an ingredient in various food formulations  and currently has a high demand in food and feed industries like bakers and commercial food companies. In India, although flaxseed is not a staple food, it is consumed by the people of North Karnataka in the form of food substitutes  such as  chutney powder, karandi etc.

Various beneficial effects associated with consumption of  whole flaxseed, ground flaxseed and its products  have become prominent.  The  potential health benefits include lowering of bad  cholesterol level, and  elevation of good cholesterol  (HDL) which results in  lowering  cardiovascular risk, diabetes, arthritis, asthma, premenstrual syndrome, allergies, multiple sclerosis,  anti cancer effects, antiviral and bactericidal activity, and antiinflammatory effect.

It has been playing a major role in the field of diet and disease  due to its Omega-3-fatty acids  and  lignan contents.

The major nutrients of flaxseed are oil and protein.  The others are concentrated in the defatted meal, commonly called flaxseed meal which is the by-product of the flaxseed crushing industry.

Flaxseed is known for its high content of protein  ( 26 percent),  dietary fiber ( 40 percent), fat ( 32 percent), and essential minerals (4 percent) as major nutritional components Flaxseed oil constitutes about 32-35 percent of the whole seed; this includes some of the biologically active essential fatty acids. It is particularly rich in  -linoleic acid (ALA), contains a lesser amount of linoleic acid (LA) an omega-6-fatty acid.

Flaxseed oil contains a mixture of fatty acids, poly unsaturated fatty acids (PUFA) 73 percent, monounsaturated fatty acids (MUFA) 18 percent, and low in saturated fatty acids 9 percent.Thus, ALA constitutes about 57 percent of the total fatty acids in oil seed, which is beneficial in some of the major health hazards  such as cardiovascular  diseases, menopausal symptoms and osteoporosis.

Lignans are wide spread diphenolic compounds in a variety of foods, particularly whole grains and legumes. Flaxseed contains high levels of lignans that have contrary biological effects, exhibiting both estrogen and antiestrogen activity and promote the production of a globulin protein and affect sex hormone metabolism.These protect against hormone sensitive cancers such as those of  breast and prostate.

Flaxseed gum, which has soluble fibre has a property of hyperglycemic and hypercholesterolemic. Lignans of flax are also implicated in the suppression of antioxidant conditions of ROS, such as hydroxyl radical, hydrogen peroxide superoxide anion, etc., in the chronic diseases. Other than antioxidant property, flaxseed lignans also cause changes in the menstrual  cycle by prolonging the luteal phase and hormone progesterone.

Flaxseed gum also has good nutritive value. In addition  its value as dietary fibre,  it plays a vital role in reducing diabetes, coronary heart disease risk, incidence of obesity, prevention of colon and rectal cancer.

Flaxseed oil causes inhibition of promotional stages of carcinogenesis of skin cancer. Also, it has a broad spectrum in the treatment of skin disorders such as eczema, acne and skin dryness
While more research is warranted in the area of flaxseed, undoubtedly flaxseed is   a promising health beneficial food ingredient, medicine, a nutritional advice and a smart food choice.

Reader (UG) in Biochemistry,   Yuvaraja's College, Mysore