Flax: Seeds, Lignans and Oil Do I need all 3?

Posted by Beth Ley Knotts, Ph.D on Sep 20th 2020

Flax is available in variety of forms, largely whole seeds, lignans, bottled oil, encapsulated oil and ground whole flax.

Personally, I avoid the pre-ground whole flax because as soon as the protective outer shell is broken, the sensitive Omega-3s inside will begin to break down and go rancid. Nobody wants to (or should) eat rancid flax seeds!!

Each form has it's benefits:


I consider flax seeds a valuable functional food rich in nutrients including lignans, antioxidants, fiber, protein, and polyunsaturated fatty acids such as alpha-linolenic acid (ALA), or Omega-3, which is difficult to obtain in the diet as it is only found in a few foods. Consuming these nutrients may help lower the risk of various conditions, such as to prevent constipation, high cholesterol, heart disease, diabetes, cancer and several other conditions.

Flaxseed also contains phytosterols. Phytosterols have a similar structure to cholesterol, but they help prevent the absorption of cholesterol in the intestines. Consuming phytosterols may therefore help reduce levels of low-density lipoprotein (LDL), or “bad,” cholesterol in the body.

It is not recommended that you eat over 1/4 cup of flax daily so if you are looking for the therapeutic benefits of the lignans or the Omega-3's you would want to add those separately.

Flax seeds have a long shelf life as long as they are kept out the heat. It is best to only grind as much as you need for your recipe so the Omega-3 do not go rancid. I add it to smoothies, bread, baked goods, pancakes, etc. also meat loaf and meat balls instead of cracker crumbs!!

Flax Lignans are extracted from the hulls (the outer portion) of flaxseed. This form does not contain the Omega-3s so there is no worry of rancidity. This form is 70 time more potent in terms of lignans than the whole seeds and there is very little lignans found in the oil products. So if you are specifically looking for the benefits of the lignans, you will definitely want this form. The primary lignan health benefits include:

1. Anti-cancer: Lignans may help protect against cancer by blocking enzymes that are involved in hormone metabolism and interfering with the growth and spread of tumor cells. Flax Lignans help reduce the growth of tumor in women with breast cancer. Flax hull lignans have also shown significant promise in lowering DHT levels in the prostate. DHT is formed when testosterone is synthesized by the enzyme 5-alpha-reductase. Regularly consuming lignans prevents testosterone from being converted to DHT by reducing the levels of 5-alpha-reductase in the body.

2. Hormone balancing:

Lignans provide a weaker, cleaner estrogen to balance any deficit or surplus. This is a benefit for women with PMS, perimenopause or menopause.

Flax Seed Oil

This is primarily a source of essential fatty acid alpha-linolenic acid — a heart-healthy omega-3 fatty acid. It has numerous health benefits such as to fight off inflammation, boost the immune system, lower cholesterol, etc.

This is an excellent option for a source of Omega-3 for those who are vegans or allergic to fish.

Personally, I prefer to purchase the oil in capsules which helps protect the oil. If you are going to purchase flax seed oil in bottles, buy only small bottles of flaxseed oil in dark bottles and store them in the refrigerator, as the oil can spoil quickly. Also, avoid using the oil past the expiration date on the label. It if smells bad, do not use and discard. It's gone bad.

Avoid heating flax seed oil in cooking. Add the oil to already prepared dishes and avoid microwaving to reheat. It does make an excellent salad dressing! (use instead of olive oil in your favorite recipes)