Plant Sources of Omega-3s
What is Flax?
Flax, a relatively new term to most health-conscious individuals, has a much longer history than one would expect. Archaeologists date the consumption of flax back to 9,000 BC. In 650 BC, Hippocrates wrote of flax's value in the treatment of abdominal pains. And in the 8th century, the medieval King Charlemagne was so convinced of flax's importance to good health that he passed laws requiring his subjects to consume it regularly.
This blue-flowered crop has proven to be quite versatile. Flax is used to make linen and fine quality papers, as lamp oil and as an ingredient in a variety of food products and supplements. The use of flax in the diet is showing more and more promise in many health conditions like cancer, arthritis, diabetes and menopause. Even more promising is the role of flax in helping the fight against heart disease.
Potential Benefits of Flax in Fighting Heart-Disease
Around 42% of flaxseed's calories come from total fat. This total fat is comprised of a mix of different fatty acids: 73% polyunsaturated fat, 18% monounsaturated fat and only 9% saturated fat. What makes this so beneficial to heart health is that the majority of the polyunsaturated fat contained in flax is in the form of alpha-linolenic acid (ALA). ALA is an essential fatty acid (meaning the human body cannot create this fat from others and must get it from foods) and a precursor to the heart-disease fighting long-chain omega-3 fatty acids eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). Flaxseed is the richest source of ALA in the North American diet and has many potential heart-disease fighting benefits:
- Reduces blood triglyceride values.
- Neutral effect on the good cholesterol, HDL.
- Reduces blood pressure.
- Reduces platelet aggregation (clot formation) within arterial lining.
- Reduces inflammatory response.
- May protect against stroke.
In addition to being the best plant source for the essential fatty acids, flaxseed is also an excellent source of soluble (viscous) and insoluble fibers, lignans (a phytoestrogen found to help protect against certain cancers), high quality protein and potassium. Because of the soluble fiber component in flaxseed, various researchers have also revealed that flax can modestly reduce both total and LDL (bad) cholesterol values.
How to Incorporate Flax into your Diet
Flaxseeds can be found at most cooperative markets, bulk-food stores, and natural health food stores or directly through a manufacturer. Below are the main forms of flax that are available in markets today.
Whole or ground flax
Known for the nutty flavor it adds to dishes, these reddish-brown or golden-yellow seeds can be added to virtually any food. Add whole or ground flax to a homemade baked good recipe; sprinkle on yogurt, cereals, soups or salads; add to trail mixes or toss into shakes. Because the outer hull of the seed is very difficult to digest, it is generally recommended that you grind or mill the whole flaxseed to get the greatest nutritional benefit. This can be done with your coffee grinder, blender or food processor to a coffee-ground consistency, or purchased already in the ground or milled form.
When baking, ground or milled flaxseed can be substituted for fat at a ratio of 3 to 1. For example, ½ cup of butter or margarine can be replaced by 1-½ cups of flax. Be aware that baked goods containing flax brown more quickly so you may want to adjust cooking times. Just want to add a little flax but don't want to replace the fat in a recipe? Use up to 2 Tablespoons of ground or milled flaxseed without altering any other ingredients, or sprinkle a little flax on top of yeast or quick breads for added crunch.
Whole flax can be stored at room temperature for up to one year. Because flax contains a significant amount of fat, the ground form can become rancid quickly. Store ground or milled flax at refrigerator temperatures for up to 3 months or grind the flax as you need it. A benefit to buying pre-ground or milled flax is that many manufacturers treat it with antioxidants, extending the shelf life.
Flaxseed oil is a wonderful form of ALA however, in the oil form it lacks the additional benefit of fiber, lignans and protein. For the benefits of ALA, add small amounts (1-2 teaspoons) of flaxseed oil to a marinade, smoothie, and shake or as a salad dressing. Flaxseed oil is sometimes difficult to find but can be purchased by ordering directly from a manufacturer or in the refrigerator section of some health food stores. Flaxseed oil becomes rancid very quickly; store in a refrigerator no more than 6-8 weeks. The shelf life is even shorter if you do not refrigerate.
Other forms of flax
Below is just a small list of some types of food products that contain flax.
- Cereals, ready-to-eat and cooked
- Energy bars
- Muffin, bread, pancake and waffle mixes
- Frozen waffles
- Omega-3 enriched eggs (hens are fed the flaxmeal)
- Snack items like chips, trail mixes and muesli
Read food label packages carefully to determine if flax is an ingredient. Most products will tell you right on the front of the package but check the ingredient's list too.
Pills and supplements
Almost as soon as a nutrient is found to have potential in fighting disease, a synthetic supplement is soon created, touting the same disease-fighting benefits. The story is no different for flax. There are currently two forms of flax sold in pill-form, one containing ground flax the other flax oil. The oil-based have the same downsides as flax oil - lacking dietary fiber, lignans and protein and having a short shelf life. The ground flax types have the same benefits as ground flax, except you need to consume several capsules (sometimes 8 or more) each day to get the same benefit that a few teaspoons of ground flax would have. That's a lot of pills!
Another downside to taking pills is that research is still in its infancy. Researchers may find years from now that there are other components in the actual flaxseed that result in health benefits. This nutrient could be lost in the processing of the pill. In addition, the Food and Drug Administration (FDA) has yet to have regulatory control over supplements, meaning there's no real oversight on their production. The prudent approach would be to wait until further research is conducted.
How Much Flax Should I Eat?
At this time there is no gold standard serving size to consume for maximal heart-protection, but as more and more research unveils the cardiovascular benefit of flax, specific dietary recommendations may be established. A prudent intake of ground or milled flaxseed is around 2-3 Tablespoons per day, added to any foods you choose. Incorporating food products containing flax is also a great way to reap its heart-healthy benefits.
Whichever form you choose, it is always best to contact your doctor and/or registered dietitian before you incorporate flax into your diet. Do not use flax as a substitute for any prescription medications you are currently taking.
Enjoy the nutty flavor and texture that flax has to offer! Let your taste buds and your heart benefit from what this versatile food has to offer.
Flaxseed (flax) is the richest source of ALA and lignans in the North American diet and is an excellent source of fiber, high quality protein and potassium.
Lignans are phytoestrogens and antioxidants that have been shown to help prevent certain diseases such as heart disease and cancer. Flaxseed contains 75 to 800 times more lignans than other plant foods.
How can I add flaxseed to my daily diet?
Flaxseed can be added to almost any food. It has a nutty flavor that goes well in many meals. The seeds are reddish-brown or golden-yellow in color. The outer hull of the seed is very difficult to digest, so you should grind or mill the whole flaxseed to get the most nutrition from it. You can grind the seeds in a coffee grinder, blender or food processor, or you can buy ground or milled flaxseed at the store.
- Use flaxseed instead of fat in a homemade baked goods. Replace 1½ cups of ground flaxseed for ½ cup butter or margarine. *Caution: Using flaxseed can cause baked goods to brown faster*.
- Use flaxseed instead of an egg when baking. Substitute one egg with 1 Tablespoon of ground flaxseed and 3 Tablespoons of water.
- Sprinkle ground flaxseed on yogurt, cereal, soup or salad.
- Add ground flaxseed to shakes and smoothies.
How much flaxseed should I eat?
Eating 2 Tablespoons of ground flaxseed per day is considered a healthy daily amount.
Because flaxseed is high in fat, the ground form can become rancid or spoil quickly. You can store ground or milled flaxseed in the refrigerator (35 º–38 º F) for up to 3 months. Whole flaxseed can be stored at room temperature for up to one year.
Chia Seeds are another source of ALA. They are also a good source of fiber, protein, calcium, magnesium and phosphorous. For hundreds of years, this tiny seed was used by the Aztecs as their main energy source. This unprocessed, nutty-tasting seed can be made into a gel and added to foods as well as used as a substitute for whole grains.
How can I add Chia seeds to my daily diet?
Unlike flaxseed, Chia seeds do not need to be ground for your body to absorb the nutrients. Some easy ways to add Chia seeds to your diet are:
- Sprinkle Chia seeds on yogurt, cereal or salad.
- Add Chia seeds to shakes or smoothies.
- Add Chia seeds to your favorite quick-bread batter.
- To boost the nutrition in homemade muffins or pancakes, substitute Chia powder for one-quarter of the flour called for in the recipe. You can buy Chia powder in stores or you can make your own by grinding the seeds in a coffee grinder.
- Chia seeds can absorb 10 times their own weight in water. So, they can also be made into gel to thicken puddings, sauces, fruit spreads or dips. You can make Chia gel by adding one-third cup of Chia seeds to 2 cups of water. Mix well for 3 to 5 minutes to avoid clumping. Place the Chia Seeds in the refrigerator in a sealed jar.
- For vegan baking, replace one egg with ¼ cup of Chia gel.
How much Chia should I eat?
Eating 1 to 2 Tablespoons of Chia seeds a day is considered a healthy daily amount.
If you decide to eat flaxseed and Chia seeds every day, it is best to slowly add them to your diet until you reach the healthy daily amounts. Both seeds are high in fiber, and eating too much too quickly can cause stomach discomfort.
Other plant-based sources of Omega-3 fatty acids
Walnuts, soy foods, pumpkin seeds, and canola (rapeseed) oil are additional sources of Omega-3 fats. These foods contain a lower concentration of ALA than flax and Chia seeds, but they can still help boost your overall ALA intake. In addition, these foods contain disease-fighting vitamins, minerals, antioxidants and dietary fiber, which are all part of a heart-healthy diet.
For more information on flaxseeds, contact any of the following:
Nutrition Program Preventative Cardiology and Rehabilitation
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