Did you know? Canada is the largest global producer of flaxseed. (5)
Flaxseed is rich in omega-3 fatty acids, fiber, and lignans.
Benefits of flaxseed
The main health-promoting components in flaxseed include fiber, lignans, and alpha-linolenic acid (ALA), a type of omega-3 fatty acid. Consuming flaxseed is associated with numerous benefits such as reduced risk of certain cancers, improved cardiometabolic and digestive health, and more. (14)Cancer risk
Flaxseeds are an excellent source of lignans. Lignans are plant compounds possessing antioxidative, anti-inflammatory, and estrogenic properties. (10) Various animal and human trials have demonstrated the protective effects of the lignans in flaxseed against breast cancer risk. (1)(8)(9) One study comparing food frequency questionnaires completed by 2,999 women with breast cancer and 3,370 healthy women noted an association between regular flaxseed consumption and reduced breast cancer risk. (8) Furthermore, a systematic review concluded that flaxseed reduced hot flashes, cell proliferation (cancer cell division), mammographic breast density, and mortality among women with breast cancer. (4) Some research suggests that flaxseed may also have positive effects on men with prostate cancer. In a study involving men with prostate cancer, daily consumption of flaxseed in combination with a low-fat diet for a six-month period was found to reduce prostate-specific antigen (PSA) levels, an indicator of how quickly the cancer may be spreading. (2)Heart health
Flaxseed has been shown to reduce low-density lipoprotein (LDL) and total cholesterol levels in patients with cardiovascular disease. In one study comparing the lipid-lowering effects of milled flaxseed consumed in addition to cholesterol-lowering medications (statins) compared to a placebo (whole wheat with statins), flaxseed lowered circulating LDL levels by 15%. (3) Flaxseed and flaxseed oil may also help improve high blood pressure (hypertension), a major cardiovascular disease risk factor. A 2015 systematic review and meta-analysis demonstrated that whole flaxseed was the most effective form of flax (compared to flaxseed oil or lignin extract) for lowering blood pressure, especially when consumed for a duration of 12 or more weeks. (6)Blood sugar regulation
Consuming flaxseed has been shown to have significant benefits for improving glycemic control. According to a 2017 meta-analysis, flaxseed, but not flaxseed oil or lignan extract, was shown to improve insulin sensitivity and blood glucose (sugar) control, especially when consumed for at least 12 weeks. (11) These effects are believed to be partly due to the soluble fiber and lignin found in flaxseed. Fiber helps regulate blood sugar by slowing glucose absorption during digestion and lignans can suppress the expression of the phosphoenolpyruvate carboxykinase (PEPCK) gene, which facilitates glucose production via the gluconeogenesis pathway. (11)Brain and mental health
Emerging human trials demonstrate the benefits of flaxseed and flaxseed oil for depression. In a 2020 randomized, double-blind, placebo-controlled clinical trial, women with depression who were given twice-daily doses of flaxseed oil for ten weeks experienced improved depression-related symptoms and increased brain-derived neurotrophic factor (BDNF) concentrations, a protein that promotes the growth, maturation, and maintenance of nerve cells. (16) Human studies are limited; however, some animal studies suggest that the omega-3 fatty acids found in flaxseed play a significant role in brain development. According to one study, rats fed flaxseed during their pregnancy gave birth to pups with heavier brains that contained more significant amounts of ALA and docosahexaenoic acid (DHA) than pups born to rats that were not given flaxseed during pregnancy. (7)Digestive health
Due to its high fiber content, flaxseed may be helpful for individuals struggling with common digestive problems such as constipation. A 2020 trial comparing the effects of flaxseed flour and a lactulose solution for patients with functional constipation found that flaxseed flour was more effective at increasing frequency of bowel movements and reducing difficulty with bowel movements as well as increasing quality of life among participants. (18) Another study noted that cookies prepared with flaxseed improved the frequency of bowel movements in patients. (17)Stay hydrated: Consuming flaxseed with too little water can worsen or contribute to constipation. Make sure to drink plenty of water when consuming flaxseed. (12)
Skin health
Studies demonstrate that consuming flaxseed and flaxseed oil may improve signs of skin sensitivity thanks to the anti-inflammatory effects of omega-3 fatty acids. In one study, patients who supplemented with flaxseed oil for 12 weeks experienced decreased skin sensitivity, roughness, and scaling, and increased skin smoothness and hydration. (13)Choosing flaxseed
Flaxseed is available in most grocery stores in both whole seed and ground varieties. For the body to properly digest flaxseed, it must be milled or ground so that the hard protective coating is no longer intact. However, once ground, the omega-3 fatty acids found in flaxseed begin to oxidize. To prevent oxidation, store ground flaxseed or flaxseed oil in an airtight container inside the refrigerator. Better yet, grind whole flaxseeds using a coffee grinder or blender as you need them. (14) Flaxseed is also available in other forms, including:- Flax milk: a suitable alternative to dairy milk for individuals with lactose intolerance or nut or soy allergies
- Flaxseed oil: extracted from flaxseeds that have been ground and pressed
- Partially-defatted flaxseed meal: a byproduct of flaxseed oil production (14)(15)
Adding flaxseed to your diet
Incorporating flaxseed or flaxseed oil into your diet is simple. Consider trying any of the following culinary possibilities.Add to a smoothie
Include whole or ground flaxseeds in your morning smoothie for a dose of fiber, omega-3 fatty acids, and plant-based protein.Did you know? 1 oz (3 tbsp) of ground flaxseed contains 6 g of protein and 8 g of dietary fiber. (19)
Bake into muffins, bread, or cookies
Flaxseed is a common addition to many baked goods, especially muffins, bread, and cookies. Did you know that flaxseed is a great egg replacer? To replace one egg in a recipe, simply mix 1 tbsp of ground flaxseed with 3 tbsp of water and let it sit for a few minutes until it creates a gel-like consistency.Heat and flaxseed: Baking flaxseed at temperatures up to 350 degrees Fahrenheit (178 degrees Celsius) for two hours does not affect the ALA composition in baked goods. (14)
When mixed with water, flaxseed turns into a gel that can be used as an egg substitute in many baked goods recipes.
Mix into oatmeal or yogurt
Just like other nuts and seeds, you can add ground flaxseeds to your morning hot cereal or bowl of yogurt.Mix into condiments
Try adding ground flaxseed to mustard or your other favorite condiment when making a sandwich or wrap.Use as a filler in homemade burgers or meatloaf
Ground flaxseed can act as a binder for many dishes such as homemade meat or veggie burgers and meatloaves without compromising texture or flavor.Whisk up a flaxseed oil salad dressing
Substitute flaxseed oil for any oil you’d typically use to make a homemade dressing. Lemon juice, balsamic vinegar, or apple cider vinegar pair well with flaxseed oil in salad dressings.Did you know? Flaxseed oil has a low smoke point, meaning it’s best to avoid cooking with it at high temperatures. When cooking, opt for oils with higher smoke points, such as avocado oil. (20)
The bottom line
Flaxseed and flaxseed oil have been shown to have antioxidant and anti-inflammatory properties, which may promote cardiometabolic, gastrointestinal, skin, and brain health. Flaxseeds are tiny seeds that can be ground into a fine powder, making it easy to add them to various foods. If you’re a patient, consult your healthcare provider before making significant changes to your diet. Is flaxseed a staple in your kitchen? We’d love to hear your favorite ways to incorporate flaxseed into your diet. Please let us know in the comments below!References
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