Flax seeds or linseeds have been eaten for thousands of years. But how nutritious are they? What is the best way to eat them? And how do they compare with flax seeds?
A previous article in this series―Can chia seeds reverse diabetes?―examined the nutritional value of chia seeds. This article will look at how nutritious flaxseeds are and compare the benefits of eating them with chia seeds.
Flaxseeds and linseeds are two different names for the same tiny seeds that have been cultivated for at least the last 6,000 years. Their colour can range from dark brown to a light gold.
The oil extracted from flaxseeds is used in the production of oil-based paints and glazing putties for windows. The oil is also used as a grain protector for wood. The high fibre content of the seeds means they can be used to add strength and durability in the making fabrics, paper and clothes.
But flaxseeds have also been eaten for thousands of years, from ancient Babylon to the Aztec Empire. They were a favourite snack of King Charlemagne of the Franks in the 8th century CE. Since the 1990s they have gained a reputation in the West as a so-called ‘superfood’.
Their reputation is well-earned. Flaxseeds are one of the richest sources of lignans (antioxidants) and plant-based omega-3 fatty acids. They are also a superior source of dietary fibre, plant-based protein, and minerals such as iron and magnesium.
They are considered one of the best foods for reducing inflammation and for maintaining the health of the gut and are usually included in diets designed to fight heart disease and similar illnesses.
How nutritious are flaxseeds?
The short answer is: highly nutritious.
100 grams of flaxseeds (linseeds) contains the following macro-nutrients:
- Calories … 534 (2236 kJ) (27%)
- Protein … 18.3g (37%)
- Carbohydrates (total) …28.9g (10%), of which:
- Dietary fibre … 27.3g (109%)
- Sugars … 1.5g
- Fat (total) … 42.2g (65%), of which:
- Saturated fat … 3.7g (18%)
- Monounsaturated fat … 7.5g
- Polyunsaturated fat … 28.7g
- Cholesterol … NIL
- Omega-3 fatty acids (total) … 22,813mg
- Omega-6 fatty acids (total) … 5,911mg
100g of flaxseeds also contains large doses of various micro-nutrients, such as vitamins:
- Thiamin (vitamin B1) … 1.6mg (110%)
- Riboflavin (vitamin B2) … 0.2mg (9%)
- Niacin (vitamin B3) … 3.1mg (15%)
- Pantothenic acid (vitamin B5) … 1.0mg (10%)
- Vitamin B6 … 0.5 mg (24%)
- Folate (vitamin B9) … 87mcg (22%)
- 7 mg
And dietary minerals … 100g also contains:
- Manganese … 2.5mg (124%)
- Magnesium … 392mg (98%)
- Phosphorus … 642mg (64%)
- Copper … 1.2mg (61%)
- Selenium … 25.4 (36%)
- Iron … 5.7mg (32%)
- Zinc … 4.3mg (29%)
- Calcium … 25mg (26%)
- Potassium … 813mg (23%)
- Sodium … 30mg (1%)
The percentages in brackets refer to recommended daily values and are based on a 2,000 calorie-a-day diet. The actual amounts of these nutrients you require will depend on your calorific needs.
Benefits of eating flaxseeds or linseeds
These seeds are a genuine superfood. Here are some of the major benefits you can get from consuming them:
- Omega-3 fatty acids
- High fibre
- Lignans (antioxidants)
- Digestive health
- Cancer prevention in women
- Weight loss
 Omega-3 fatty acids
Flaxseeds contain a form of omega-3 fats called Alpha-linolenic acid (ALA) which has anti-inflammatory properties. Studies published by the US National Library of Medicine National Institutes of Health in 2005 show that ALA can reduce the risk of coronary heart disease, reduce inflammation, promote healthy cell functioning and reduce heart arrhythmias among other benefits.
Fish oil contains EPA and DHA, two omega-3 fatty acids that can only be obtained from animal food but which are critical for optimal health. Approximately 20% of ALA can be converted into EPA but less than half-a-percent can be changed into DHA, according to a study published in the American Journal of Clinical Nutrition in September 2008. This means that ALA is sufficient to raise Omega-3 levels.
Gender and age play a key role in how much ALA is converted. The same study in September 2008 found that young women converted ALA into EPA at a rate that was 2.5 times greater than men!
 High fibre
Flax is extremely high in both soluble and insoluble fibre. Eating two tablespoons of flaxseeds a day will provide at least 20% of your need for fibre.
Because the fibre found in flaxseeds cannot be broken down during digestion, some of the calories contained in flax can’t be absorbed. This may help with weight reduction and the detoxification of the colon. It also tends to reduce cravings for sugar, a heartening fact for diabetics.
Flax contains high levels of mucilage gum. This water-soluble fibre forms a gel in your stomach and moves through your gastrointestinal tract undigested. The mucilage prevents the stomach from emptying quickly into the small intestine. As well as increasing the amount of nutrients you absorb, this makes you feel fuller and perhaps prevent you from overeating.
 Lignans (antioxidants)
Flaxseed is packed with antioxidants, specifically the type called lignans which are fibre-related.
Oxidation is a chemical reaction that can produce free radicals, unstable atoms or molecules that are highly reactive chemically towards other substances. The creation of free radicals can lead to chain reactions that can damage cells.
An antioxidant is a molecule that inhibits the oxidation of other molecules. Lignans help reduce the damage caused by free radicals. They help regenerate cells and have anti-aging properties. Thus they are vital in protecting your cells from becoming cancerous.
Lignans are fund in unprocessed plant foods including seeds, whole grains, beans, berries and nuts. Smoking, obesity, poor gut health and the use of antibiotics can affect the levels of lignans circulating in your body.
Lignans also have antibacterial and antiviral properties. Thus consuming flaxseeds can help reduce colds and bouts of flu.
Lignans can also support the growth of probiotics in the gut according to studies published by the US National Library of Medicine National Institutes of Health in 2012.
Flaxseeds, taken regularly, can reduce your cholesterol levels, according to a study published in Nutrition and Metabolism in February 2012. It does so by increasing the amount of fat excreted through bowel movements.
The study of 17 subjects found that drinking a flaxseed drink lowered fasting total-cholesterol and LDL-cholesterol by 12 and 15%, respectively, and increased the excretion of faecal fat and energy by 50 and 23%. This is because the soluble fibre in flaxseed traps fat and cholesterol in the digestive system so it’s can’t be absorbed.
The soluble fibre also traps bile, which is made in the gallbladder from cholesterol. The bile is then excreted which forces the body to make more. This, in turn, uses up excess cholesterol thus lowering cholesterol in the blood.
 Digestive health
The ability of flaxseeds to promote digestive health has been well researched.
When you excrete, your stool should evacuate like toothpaste coming out of a tube, soft and with little resistance. The fact that 27% of the seeds are fibre means that eating flaxseeds is one of the best natural remedies for constipation.
To keep yourself regular, you can add whole or ground flaxseeds to your porridge or smoothie in the morning or take a few tablespoons of flaxseed oil in a glass of fruit juice. This will also give you a large dose of magnesium which will help hydrate your stool and relax the muscles of your gastro-intestinal (GI) tract.
Flaxseeds support your digestive health in several other, well-researched, ways. For example, the ALA in flaxseed can help reduce inflammation and protect the lining of your GI tract.
Flaxseed can also be beneficial to persons suffering from digestive ailments such as Crohn’s disease (an inflammatory bowel disease). The seeds promote beneficial gut flora and provide food for bacteria in your colon that help cleanse waste from your system.
 Cancer prevention in (mainly) women
When flaxseeds are consumed as part of a healthy diet they may be able to prevent certain types of cancer, including breast, prostate, ovarian and colon cancer.
According to a study published in Clinical Cancer Research in May 2005, dietary flaxseed has the potential to reduce tumour growth in post-menopausal patients with breast cancer.
Other studies have shown that women reduce their risk of developing breast cancer when they eat large quantities of dietary fibre, lignans, carotenoid antioxidants (pigments that give fruits and vegetables such as carrots their vibrant orange, yellow, and green colours), stigmasterol (a steroid derived from plants), vegetables and poultry. For this reason, some doctors now recommend plant-based diets for reducing the risks of cancers related to unbalanced hormones.
Another study published in June 2013 in the Journal of Nutrition found that the lignans in flaxseeds may also reduce the risk of ovarian and endometrial cancers. The endometrium is the lining of the uterus.
 Weight loss
Since flaxseeds are full of healthy fats and fibre, it can help you feel full for longer. Thus you may end up eating fewer calories overall, thereby reducing your weight.
An inflamed body tends to hold on to excess weight. ALA helps reduce inflammation … another way flaxseeds may help you reduce your weight.
Thus adding a few teaspoons of ground flaxseed to your soups and smoothies on a daily basis should have a positive effect on your weight.
There are other benefits of consuming flaxseeds on a regular basis:
The copious amounts of B vitamins, along with essential fatty acids, in flaxseeds reduce the flakiness of dry skin and improve acne and eczema. These vitamins make hair and nails stronger, more resistant to damage. The seeds lubricating effects reduce dry eyes. In addition, Flaxseed oil, mixed with essential oils, can be used as a skin moisturiser.
Flax does not contain any gluten. Thus flaxseeds are useful when cooking for persons who have celiac disease or are otherwise sensitive to gluten.
How to consume flaxseeds
You can buy packets of linseeds (aka flaxseeds) in most supermarkets these days.
There are three ways you can consume the seeds. As:
- whole seeds
- ground seeds
- sprouted seeds
Whole seeds … eating whole flaxseeds will not deliver all the nutrients found in the seeds as these seeds will mostly pass through your digestive system undigested. Thus it is best to eat them ground or sprouted.
Ground seeds … you can grind flaxseeds in a coffee or spice grinder. You should do this just before they are eaten to avoid exposing them to air for too long. However, you can keep them in a rightly sealed container in the fridge for a few days.
Sprouted seeds … consuming sprouted flaxseeds is the best way to get all the nutrients in the seeds. Soaking causes the seeds to sprout and you end up with a gel-like mixture of seeds and water. It also eliminates phytic acid.
Phytates (and phytic acid) are antioxidant compounds found in whole grains, legumes, nuts and seeds.
The chief concern about phytates is that they can bind to certain dietary minerals including iron, zinc, manganese, and, to a lesser extent, calcium and slow their absorption. Eliminating phytic acid from the seeds can greatly improve the absorption of these dietary minerals.
To get them to sprout, the Flax Council of Canada recommends soaking flaxseeds for at least 10 minutes in warm water or for two hours in cold water. Some people soak the seeds overnight and then add the resulting goo to their morning porridge or other breakfast food such as a morning smoothie.
Whichever way you choose to consume flaxseeds, remember that they absorb lots of water. So you need to take them with plenty of water or other fluids.
There are many ways you can incorporate flaxseeds to your diet … add them to homemade bread and sugar-free cookies, mix them into your smoothies, whip a tablespoon into a bowl of yoghurt or use as a substitute for egg in vegan dishes.
Because the seeds can absorb a lot of liquid they help bind ingredients in baking recipes.
Which is best: flaxseeds or chia seeds?
Both flax seeds and chia seeds have lots to recommend them. Both can absorb lots of water, make you feel full, prevent constipation and help with your digestive health.
But they differ in three important respects:
- Alpha-linolenic acid (ALA)
ALA … 100 grams of flaxseeds contains about 21,000 milligrams of ALA, whereas 100g of chia seeds contains only 17,300mg of ALA, nearly 20% less. So flaxseeds are a better source of ALA.
Fibre … 100 grams of flaxseed contains just over 28 grams of fibre, whereas the same amount of chia seeds contains over 38 grams.
Though flaxseeds contain less fibre than chia seeds, both seeds form a gel when they are mixed with liquid. The gel blocks the fibre from being broken down and releasing sugars which helps you control your blood glucose. Both seem to be equally good at helping bowel movements and lowering cholesterol.
Lignans … antioxidants, which help prevent the damage caused by free radicals, are only found in high levels in flaxseed. However chia seeds contain other antioxidants.
Further comparisons can be made between the two types of seeds. For example, flaxseeds contain more protein than chia seeds. However chia seeds contain more calcium than flaxseeds.
The choice between the two seeds is not clear-cut … in fact, it is a bit of a toss-up though, for my money, I plump for flaxseeds.
However both would appear to be equally useful for controlling blood glucose levels and beating diabetes.