Everything you wanted to know about flax but were afraid to ask
Flax seeds and their oil have been showing up in everything these days, from tortilla chips and crackers, to energy bars, cereals and peanut butter. Even the chicken feed that your egg-laying hens are eating is being supplemented with flax. Food manufacturers love tossing in some flax seed so that they can make health claims about Omega-3 fatty acid content. The question is: Why should you care?
First, let’s meet the flaxseed.
It’s an oilseed, for starters. It’s rich in a type of unsaturated, long-chain fatty acids called Alpha Linolenic acid (ALA), which you may have heard referred to as an omega-3 fatty acid. These omega-3 fats are also called essential fatty acids because our bodies need them, but cannot manufacture them. Flax seeds and walnuts are the 2 best vegetarian sources of these essential fatty acids, so if you’re a vegetarian–or perhaps an omnivore that doesn’t eat 2 servings of fatty fish per week–flax is great addition to your diet.
Since unsaturated fats are much less stable than saturated fats (think olive oil vs. Crisco), they are very sensitive to oxidation by light and heat. That’s why flax seed oil is sold in dark or opaque containers and is usually refrigerated; these measures help keep it from spoiling. Similarly, most ground flax seeds–whose oils (fats) have been exposed to the air through the grinding process– are sold in vacuum-sealed packages; once you open them, keep them refrigerated and use them within a few weeks, or freeze them. The most stable way to buy flax seeds would be in whole seed form; however, this means you will have to grind them before using them (a little coffee grinder works great for this purpose). This is why food manufacturers usually use whole flax seeds when adding them to food: any other form would impair the shelf-life of their product. But eating whole flax seeds offers minimal nutritional benefit, as the sturdy seed coat protects the seeds from your digestive enzymes. As a result, most flax seeds will pass through your digestive system intact without being digested. So if you’re relying on tortilla chips or crackers with whole flax seeds to help provide you with your daily omega-3 needs, you may want to reconsider.
And what’s so important about omega-3′s?
First, they are necessary structural components of cell membranes. As such, they are essential to normal growth and development. There are present in high concentrations in the brain and the eyes, which means that an adequate intake of these essential fats is especially important to maintain optimal cognitive function and vision.
Second, they are precursors to a group of biologically-active substances, called eicosanoids, that have a critical role in regulating inflammatory responses throughout the body. Eicosanoids made from omega-3 fatty acids, like the ones in flaxseed, tend to counteract inflammation, both by promoting anti-inflammatory reactions (like dilating blood vessels to prevent high blood pressure or preventing platelets from aggregating in the blood, which can cause dangerous clots) AND competing with the pro-inflammatory omega-6 fats for a home in your cell membranes.
As you may have surmised, diets rich in omega-3 fats are associated with decreased risk for all sorts of inflammatory diseases, with the evidence strongest for a decreased risk of cardiovascular disease, coronary heart disease and certain types of stroke. This means that foods rich in omega-3 fats are an especially good choice for people who have a history of these diseases, or who have risk factors for these diseases, such as high cholesterol, high triglycerides, high blood pressure or diabetes. There is also some evidence to support a role of omega-3 fats in improving symptoms of other inflammatory conditions, like rheumatoid arthritis and ulcerative colitis.
Flax seeds and Omega-3′s
The type of omega-3 fatty acid that flax seed contains is called ALA. ALA is a form of omega-3 fatty acid found in plants; the other major food source is walnuts. Our bodies need ALA as a precursor to make 2 even longer fatty acids called EPA and DHA. By now, you may be thinking that this is a pretty inefficient way to get EPA and DHA, and you’d be right. While ALA is an essential precursor to EPA/DHA, the conversion rate is very inefficient: only about 10% of the ALA is actually converted into EPA/DHA. This is why fish and fish oil supplements are so much more popular than flax seeds: Fatty fish, like salmon, mackerel, herring, sardines and anchovies are excellent direct sources of EPA and DHA, in the exact form you need them, ready to go. In fact, most research that studies the role of omega-3 fats on disease uses fish oil supplements for this exact reason.
How much omega-3 do you need?
When it comes to omega-3, two things matter. One: the actual amount of omega-3 fats that you eat. In this case, the recommended intake of ALA is 1.6g for men and 1.1g for women per day, which you can easily meet with just 1 tsp of flaxseed oil, 1-2 TBSP of ground flaxseeds or 1 oz (~1/4 cup) of walnuts. Easy!
The second thing that matters is the ratio of (pro-inflammatory) omega-6 fats and (anti-inflammatory) omega-3 fats in your diet. An ideal ratio would be somewhere between 1:1 and 4:1. In the typical western diet, the average ratio is closer to 10:1. (Yowza!) It is believed that this is one important factor behind the high rates of cardiovascular disease, heart disease and stroke in Western countries. Omega-6 fatty acids come from vegetable oils–including the ubiquitous refined corn and soybean oils used heavily in packaged snack foods, fast foods and restaurant foods. So replacing corn or soy oils with canola oil (which has some ALA) or olive oil when you cook at home, eating at least 2 servings of fatty fish per week, and/or incorporating small amounts of flax or walnuts into your daily diet will help you improve your ratio.
Flax seeds also have fiber
2 TBSPs of ground flax seed sprinkled onto anything you eat will add 5g of fiber in an instant! (That’s about 20% of a woman’s daily need.) This makes it an especially good addition to the diets of people with celiac disease, since many gluten-free grain products are notoriously low in fiber. (Oh, Did I mention flax was gluten-free?) The fiber in flaxseeds is associated with a reduced risk for cardiovascular disease, possibly through having an effect on lowering “bad” (LDL) cholesterol levels. Diets high in fiber are also beneficial for all of the regular reasons, like helping things move along properly in your intestines (which reduces constipation and reduces the risk of colon cancer.)
If you’re interested in giving flax a chance, there are lots of ways to incorporate it into your diet:
Ground flax seeds taste nutty, so add them to foods where this taste profile would fit.
- Sprinkle ground flax seeds onto yogurt, onto cold cereal, onto oatmeal or hot cereal (after its cooked), into smoothies, into bean dishes or soups, or atop cooked vegetables you might usually top with nuts (e.g., string bean
- Add ground flax seeds into baked goods, especially breads or muffins. (Try this recipe for a tasty high-fiber flax muffin that will sneak some omega-3′s into your breakfast deliciously.) I’d pair this with some low-fat yogurt for breakfast or an afternoon snack for a nicely-balanced ~300-ish calorie change from my usual routine. It’s an interesting recipe, as it calls for no added oils or fats. All of the fat in the muffin comes from the flax and the nuts, which means that it’s almost entirely heart-healthy unsaturated fat. When I made them, I cut the brown sugar down to 3/4 cup–which made for a just-sweet-enough muffin. (If you prefer a sweeter muffin, you may want to keep the full 1 cup…or better yet you can spread a thin layer of fruit butter or natural fruit preserves onto your baked reduced-sugar version.) If you like walnuts, use them as the chopped nuts that the recipe calls for and you’ll squeeze even more omega-3′s into this little muffin. To make these muffins gluten free, I substituted the wheat flour for GF all-purpose flour and the oat bran with hazelnut meal. I also used chopped hazelnuts as my nut to keep with the general theme.)
- Try this famous vegan baking trick: replace one egg in a baking recipe with 1 TBSP ground flaxseed + 3 TBSP warm water, mixed together.
- Add 1 tsp of flaxseed oil into a smoothie or onto a salad. (Note: do not cook with flaxseed oil or add it to hot food, as the heat will destroy its beneficial properties and make it taste “off”.)
Where to find Flax
Any health food store or supplement store (e.g., GNC) will sell at least one form of flax seeds. (Note: only buy the oil if its been refrigerated!) Many better supermarkets –like Whole Foods–will also sell whole or ground flaxseeds. Several national brands market flax seeds: Bob’s Red Mill and Arrowhead Mills, for example.