Health Benefits and Nutritional Value of Flaxseed-a Review

Abstract

Flaxseed, or linseed (Linum usitatissimum L.), comes from the flax plant, which is an annual herb. The ancient Egyptians used flaxseed as both food and medicine. The Latin name of flaxseed (Linum usi-tatissimum L.) means " very useful " , and it has two basic varieties: brown and yellow or golden (also known as golden linseeds). This review highlights the potential of 'flax seed' as a 'neutraceutical' and its role as a protective and therapeutic medicinal food.

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INDIAN JOURNAL OF APPLIED RESEARCH X 243
Volume : 6 | Issue : 1 | JANUARY 2016 | ISSN - 2249-555X
ReseaRch PaPeR
Health Benefits and Nutritional Value of Flaxseed- a
Review
Sadia Chishty Monika
Research Scholar, Department of Home Science,
University of Rajasthan, Rajasthan
Research Scholar, Department of Home Science,
University of Rajasthan, Rajasthan
Home Science
Keywords
Flaxseed, Benefits, omega-3 fatty acids, cardiovascular disease
ABSTRACT Flaxseed, or linseed (Linum usitatissimum L.), comes from the flax plant, which is an annual herb. The
ancient Egyptians used flaxseed as both food and medicine. The Latin name of flaxseed (Linum usi-
tatissimum L.) means “very useful”, and it has two basic varieties: brown and yellow or golden (also known as golden
linseeds). This review highlights the potential of ‘flax seed’ as a ‘neutraceutical’ and its role as a protective and thera-
peutic medicinal food.
Introduction
Flaxseed is one of the most important oilseed crops for in-
dustrial as well as food, feed, and fiber purposes. Almost
every part of the flaxseed plant is utilized commercially,
either directly or after processing. The stem yields good
quality fiber having high strength and durability. The seed
provides oil rich in omega-3, digestible proteins, and lig-
nans. In addition to being one of the richest sources of
α-linolenic acid oil and lignans, flaxseed is an essential
source of high quality protein and soluble fiber and has
considerable potential as a source of phenolic compounds.
Flaxseed is emerging as an important functional food in-
gredient because of its rich contents of α-linolenic acid
(ALA), lignans, and fiber. Lignans appear to be anti-carci-
nogenic compounds. The omega-3s and lignan phytoestro-
gens of flaxseed are in focus for their benefits for a wide
range of health conditions and may possess chemo-protec-
tive properties in animals and humans.
Materials and methods
The data presented in the review paper were collected us-
ing all scientific data come from articles, journals and web-
sites such as Google scholar, Scopus and Puvmed.
Cullnary Uses of Flax seed
Flaxseed meal is gluten free and has a pleasant nutty fla-
vour. The protein content, combined with the gelling/bind-
ing properties of the soluble fiber found in flaxseed meal,
make it ideal for incorporating into gluten free baked
goods, or as a gluten free thickening agent.
One tablespoon of flaxseed meal combined with three ta-
blespoons of water and allowed to gel can even be used
as a substitute for an egg in baked goods. The flake is
quite good combined with hot or cold breakfast cereals in
the morning and is a good source of fiber.
Applications as a dietary supplement
• Isolatedencapsulated lignansupplements.
• Fiber supplementation (bulk laxative with a demulcent
action).
• Asa componentof proteinpowderblends.
Applications as a food ingredient
• Breads and other baked goods such as cookies and
muffins including gluten free products. The incorpo-
ration into bread results in an improved texture and
crumb structure.
• Healthy functionalsnack foodssuch ashighproteinen-
ergy bars.
Nutrient in Flaxseed
Table 1. -Nutritional value of Flaxseed
Quantity Per
Serving(5 gm) Quantity Per Serv-
ing(100 gm)
Energy 82kj 1635 kj
Protein 1.6g 32g
Total Fat 0.5g 10g
Saturated 0.02g 0.4g
Monounsaturated 0.08g 1.5g
Polyunsaturated 0.35g 7g
Omega 3(ALA) 0.25g 5g
Total Carbohydrate 2.18g 43.6g
Sugar 0.07g 1.4g
Dietary fibre 1.95g 39g
Soluble fibre 0.4g 8g
Insoluble fibre 1.55g 31g
Lignans 25-50mg. 500-1000mg
Typical chemical analysis of flaxseed fibre. Data averaged
from analyses undertaken by an independent NZ labora-
tory.
Omega-3 fatty acids
There is an optimal ratio of omega-6 to omega-3 in the
human diet. Oils such as flaxseed, walnut, and canola help
to maintain this balance. Whilst it is true that very little
ALA converts to the long chain polyunsaturated omega-3
found in marine oils, it does have
beneficial effects itself. The benefits of ALA are seen at in-
takes as low as 1g/day and 2g/day is recommended for a
cardio protective effect.
Researchers are investigating whether omega-3 fatty ac-
ids contained in flaxseed may help protect against certain
infections and in treating conditions including ulcers, mi-
graine headaches, attention deficit/hyperactivity disorder,

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eating disorders, preterm labor, emphysema, psoriasis,
glaucoma, Lyme disease, lupus, and panic attacks
Proteins
The amino acid pattern of flax protein is similar to that of
soybean protein, which is viewed as one of the most nu-
tritious of the plant proteins. Like all vegetables, flaxseed
proteins have techno-functional properties that affect their
behaviour in a food system through interaction with other
ingredients.
These properties are mainly dependent on their hydration
mechanisms for solubility and water⁄oil retention capacity.
The amino acid pattern of flax protein is similar to that of
soybean protein, which is viewed as one of the most nu-
tritious of the plant proteins. Flaxseed grain and flaxseed
paste contain about 21% and 34% protein respectively
and may varies with the genetic and environmental fac-
tors. Cool climates usually result in high oil and low pro-
tein content in the seeds. Flaxseed has two major stor-
age proteins, a predominant salt soluble fraction with high
molecular weight (11-12S; globulin; 18.6 % nitrogen) and a
water soluble basic component with low molecular weight
(1.6- 2S; albumin; 17.7 % nitrogen) .
Dietary fiber
Flaxseed meal is high in fibre, a significant amount of
which is soluble (20%), in the form of gums and mucilages.
In addition to accounting for the laxative effect of flaxmeal,
soluble fibre is known to have potent cholesterol lowering
qualities, therefore reducing a major risk factor for cardio-
vascular disease. In Canada, where a great deal of research
has been carried out, there is now an approved health
claim for the use of ground flaxseed to lower cholesterol.
Insoluble dietary fibre reduces insulin resistance, is useful
in treating constipation and helps maintain overall bowel
health. Increased stool bulk, normalised bowel transit time,
healthy gut flora, and production of short-chain fatty acids
such as butyrate are all positive effects on the bowel of a
high fibre diet. Low fibre diets are associated with many
chronic diseases including inflammatory bowel disease,
heart disease, obesity, diabetes and colorectal cancer. The
fibre content of flaxmeal makes it an ideal addition to a
balanced diet aimed at reducing the risk of these chronic
diseases.
Carbohydrates
Flax is low in carbohydrates (sugars and starches), provid-
ing only 1 gram (g) per 100 g. For this reason, flax contrib-
utes little to total carbohydrate intake; it’s recommended
for people with specific deseases. Flaxseed polysaccharide
is composed of two major fractions: a neutral arabinoxylan
(75%) and an acidic rhamnogalacturonan (25%). The ara-
binoxylan is composed mainly of xylose, arabinose, and
galactose and the rhamnogalacturonan consists of L-rham-
nose, D-galactose, D-galacturonic and L-fucose acid. Con-
siderable and significant variations exist in monosaccharide
composition, carbohydrate yield and quality among acces-
sions from the world collection of flaxseed .
Health benefits
Flaxseed is well-known for the content of chemical com-
pounds with specific biological activity and functional
properties: polyunsaturated fatty acids (PUFA) omega-3
family, soluble dietary fibers, lignans, proteins and carbohy-
drates. However,it is constituted by few levels of adverse
health compounds such as Cadmium, protease inhibitors
and cyanogenic compounds
Flaxseed and Cancer
Ground flax seeds have been studied for its effect on can-
cer, including several excellent studies by Lilian Thomp-
son’s research group at the University of Toronto. In one
study the flax seed, its lignan fraction, or the oil were add-
ed to the diet of mice who had previously been admin-
istered a chemical carcinogen to induce cancer. All three
treatments reduced the established tumor load; the lignan
fraction containing secoisolariciresinol diglycoside (SDG)
and the flax seed also reduced metastasis. In another
study the flax lignan SDG was fed to mice starting 1 week
after treatment with the carcinogen dimethylbenzanthra-
cene. The number of tumors per rat was reduced by 46%
compared to the control in this study. Flax or its lignan
(SDG) were tested to see if they would prevent melanoma
metastasis. The flax or lignan fraction were fed to mice two
weeks before and after injection of melanoma cells. The
flax treatment (at 2.5, 5, or 10% of diet intake) resulted in
a 32, 54, and 63 percent reduction in the number of tu-
mors, compared to the control. The SDG, fed at amounts
equivalent to the amount in 2.5, 5, or 10% flax seed, also
reduced the tumor number, from a median number of 62
in the control group to 38, 36, and 29 tumors per mouse
in the SDG groups, respectively.
Flaxseed and Heart Disease
Flaxseed has recently gained attention in the area of
cardiovascular disease primarily because it is the rich-
est known source of both alpha-linolenic acid (ALA)
and the phytoestrogen, lignans, as well as being a
good source of soluble ber. Human studies have
shown that flaxseed can modestly reduce serum to-
tal and low-density lipoprotein cholesterol concentra-
tions, reduce postprandial glucose absorption, decrease
some markers of inflammation, and raise serum levels
of the omega-3 fatty acids, ALA and eicosapentaeno-
ic acid. Data on the antiplatelet, antioxidant, and hypo-
tensive effects of flaxseed, however, are inconclusive.
Partially defatted flaxseed reduced total cholesterol (4.6 ±
1.2%; P = 0.001), LDL cholesterol (7.6 ± 1.8%; P < 0.001),
apolipoprotein B (5.4 ± 1.4%; P = 0.001) and apolipopro-
tein A-I (5.8 ± 1.9%; P = 0.005), but had no effect on se-
rum lipoprotein ratios. There were no significant effects on
serum HDL cholesterol, serum protein carbonyl content,
or ex vivo androgen or progestin activity. Unexpectedly,
serum proteinthiol groups were significantly lower (10.8 ±
3.6%; P = 0.007) suggesting increased oxidation. Dietary
flaxseed has been shown to have potent antiatherogenic
effects in rabbits. When LDL receptor deficient mice (LD-
LrKO) were administered a 10% flaxseed-supplemented
diet for 24w, a reduction of circulating cholesterol levels
was observed indicating the anti-atherogenic effect of flax
seeds.
Flaxseed and Menopause
Competition of lignans with estrogen for receptor sites
causes dual effects. Considering that lignan possesses a
weak hormonal action, during phases of life when there
is a large production of estrogen, the chronic ingestion
of flaxseed may exert an antiestrogenic action because it
competes with estrogen for the same receptors. By means
of this mechanism, flaxseed may protect women with risk
of cancer by decreasing hormonal signalization involved in
the beginning of tumor development Consuming lignans
may lower the risk of endometrial cancer in post-meno-
pausal women, and it might also help reduce the severity
of osteoporosis. Dew et al. 2013 sistematic review con-
trolled flax interventions on menopausal symptoms and

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bone health in premenopausal and postmenopausal wom-
en. The majority of studies considered suggested that flax
consumption alters circulating sex hormones and increased
the urinary 2α-hydroxyestrone/16α-hydroxyestrone ratio as-
sociated with a lower risk of breast cancer. However, few
studies considered bone mineral density or markers of
bone turnover; more investigation needed to confirm influ-
ence of flax lignan intake on postmenopausal bone mineral
density.
Conclusion
Flaxseed has many health benefits as well as rich of nutri-
ents. In fact the content Fiber, proteins, Amino acids, vi-
tamin E and lignans present in flaxseed satisfy basic needs
in the human diet. Flaxseed also has healthy properties
that prevent from cardiovascular disease, problems related
to menopausal and many more disease
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