Flaxseeds and Flaxseed Oil…Practical Pointers
by Brenda Davis, R.D.
Flaxseeds have the highest alpha-linolenic acid content of any food – 57% of the oil in flax is alpha-linoleic acid (omega-3). They contain about 3½ times as much omega-3 fatty acids as omega-6 fatty acids. Flaxseed oil provides approximately 2.5 g of this essential fatty acid per teaspoon. One tablespoon of flaxseeds contain about a teaspoon of oil. Flaxseeds also provide abundant fiber, about 60% of which is soluble fiber (the type of fiber that is especially effective in helping control blood sugar levels and reducing blood cholesterol levels). It is also the richest known source of lignans, phytoestrogens that are potent anticarcinogens. Flaxseeds are also rich sources of potassium, magnesium and boron.
The oil from flaxseeds is highly unsaturated, thus will be easily damaged upon exposure to light, heat or oxygen. On the other hand, the whole seeds are protected by a hard outer coat and will last for many months in your pantry. Unfortunately, because the seeds are so small, they generally enter the gastro-intestinal system intact, and leave little worse for the wear. To enhance the digestibility of flax seeds simply grind them in a blender or a coffee grinder.
Storage and Use of Ground Flax Seeds
Flax seeds can be purchased in the bulk section of natural food stores and in most large grocery stores. Once flax seeds are ground they go rancid more quickly, thus should be stored in the refrigerator or freezer. Flax seeds absorb 5 to 6 times their weight in water, so it is especially important to drink plenty of fluids when consuming ground seeds.
Ground flax seeds can be sprinkled on salad or cereal (the soluble fiber in the seeds will make the liquid in your cereal very thick if it sits for too long). If you add flax to cooked cereal, do so at the end of cooking.
One of the most exciting uses for ground flax is as an egg replacer. One tablespoon of ground flax plus 3 tablespoons of liquid replaces one egg in baking. This works especially well in muffins, pancakes, cookies and cakes (where eggs are not an essential ingredient!).
1 Tbsp. ground flax seeds + 3 Tbsp water (or other liquid) = 1 egg
Storage and Use of Flax Oil
Flax seed oil can be purchased in the refrigerator section of natural food stores. It is packaged in black plastic bottles or dark brown glass bottles to protect it from light. The oil must be kept refrigerated and will stay fresh for up to 6 weeks after opening (check expiry date). Flax oil that will not be used within this time should be frozen (it lasts for a year or more in the freezer). Rancid flax oil will smell “skunky” and should be discarded.
Flax oil should not be exposed to direct heat, as in frying or sautéing, as this will damage the oil. However, there are numerous ways you can enjoy flax seed oil:
- As a base for salad dressings
- Mixed with margarine to make an omega-3 rich spread
- Sprinkled on pasta, rice or other grains, potatoes, vegetables or popcorn (try garlic/chili flavored oil)
- In dips (i.e. tofu or yogurt dips), spreads (i.e. humus) and blender drinks
- Added to mashed potatoes or cooked cereal Safety of Flaxseeds
Raw flaxseeds contain cyanogenic glycosides, which are converted in the body to thiocynanates (also breakdown products of glucosinolates in cruciferous vegetables). Thiocyanates can inhibit the uptake of iodine by the thyroid, but this is not generally a problem when iodine is plentiful in the food supply. However, under conditions of chronic low iodine intake, large amounts of raw flaxseeds could contribute the goiter. Cooking flaxseeds destroys the cyanogenic glycosides.Flax Oil Dressing
Mix ½ cup flax oil, 3 Tbsp lemon juice, 3 Tbsp water, 2-3 garlic cloves, ½ tsp sugar (or other sweetener), 1 tsp Dijon mustard, 1 tsp light miso (optional), 5 ml Bragg’s Aminos or tamari sauce and 2 Tbsp fresh herbs (or 1 tsp dried). Place everything in a blender. Puree until smooth. Cover and refrigerate up to one week.