What are Fatty Acids?
These are lipid molecules that are essential for good health, and some of them can be found in foods. They're called 'long-chain' fatty acids because of the chains of lipid structures that make them up. Found in plants, animal fats and vegetable oils, fatty acids are also used in other areas besides nutrition. They play a role in cooking, are found in health products and cosmetics, and are widely used industrially.
What are Omega-3 Fatty Acids?
Omega-3s are a class of fatty acids called polyunsaturated fats (PUFAs). These fats have a type of double bond structure that our bodies can't mimic, and this formation gives them the ability to interact with important metabolic processes in the body. Alpha-linoleic acid (ALA) is the simplest omega-3, and it's the one that the body can't produce under any circumstances. However, at times, ALA can be transformed into eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). These are the heavy-hitters that protect us from poor health and chronic disease.
Linoleic acid (LA) is an omega-6 fatty acid and alpha-linoleic acid (ALA) is an omega-3 fatty acid. These are two of the building blocks of good health. They're referred to as essential because they're both vital components of metabolic functions in the body, and a deficiency in either one will lead to health problems. Polyunsaturated fatty acids like these can't be produced in the liver where many other fatty acids are formed.
Why are Omega-3 Fatty Acids So Important?
Both omega-3 and omega-6 fatty acids are vital nutritionally, but it takes more planning to make sure you get enough of the omega-3 kind. They're used in cell membrane formation, and they assist blood circulation, as well as playing a role in the availability of oxygen. Women and men over age 14 should get at least 1.1 and 1.6 grams of omega-3 each day.
Where Are Omega-3s Found?
Flaxseeds and walnuts are good sources of omega-3 fatty acids, as are canola and olive oil. Whole grains, beans and vegetables also have them in smaller amounts. Fish are a popular source, but they contain other fats and don't have as much fiber as nut, grain and vegetable sources of omega-3. However, fish contain the EPA and DHA forms of omega-3 that are used to form cell membranes and perform other vital functions in the body. Most of the plant-derived ALA omega-3 is used by the body for energy, so both marine and plant-based omega-3s are valuable nutritionally.
The two primary omega-3 fatty acids in fish oil, EPA and DHA, aren't available in plants. Albacore tuna and swordfish both make the list of seafood high in omega-3s, but they also contain high levels of mercury, so they should be avoided. Farmed salmon has more omega-3 than wild salmon, but it also has a higher fat content, including saturated fat.
Here are some of the top sources of marine omega-3 fatty acids:
Wild Salmon |
1,774 |
|
Anchovies |
1,200 |
|
Halibut |
740 |
|
Mussels |
665 |
|
Oysters |
585 |
|
Trout |
581 |
|
Light Tuna |
228 |
What Are Some of the Benefits of Omega-3s?
Omega-3 fatty acids have been identified as crucial for maintaining vision and preventing inflammatory diseases like arthritis and Crohn's disease. Here are some of the other known benefits of omega-3s for human health.
Heart Health
Omega-3 fatty acids lower the levels of the damaging cholesterol LDL, lowering the risk of heart disease. This is one of the most strongly supported benefits of including omega-3s in your diet. Both EPA and DHA lower the risk for heart disease, heart attack and stroke. Unfortunately, the typical American diet is higher in omega-6 fatty acids and lower in omega-3s. This can be overcome by making an effort to balance the ratio between the two.
Flax seeds are an excellent source of omega-3s and they're easy to incorporate into your diet. They not only provide omega-3 support, but they're also rich in fiber that benefits the heart and digestive tract. They should be stored whole and ground in small amounts when used in smoothies, added to oatmeal or eaten alone as a porridge. This goes for all seeds and nuts, as grinding them exposes them to oxidization and significantly decreases their ALA content unless they're used right away
Fetal Growth and Development
Research points to omega-3s playing an important role in fetal development, especially the brain. Infants need this fatty acid for normal growth in all of their tissues. Pregnant women with increased omega-3 intake may have offspring with improved cognitive abilities. Once the child is born, breast milk is a source of omega-3 for the infant, especially if the mother is taking supplements.
Memory and Cognition
The membranes surrounding neurons are composed primarily of one of the omega-3 fatty acids, docosahexaenoic acid. There's evidence that the type of omega-3s derived from fish benefit conditions like the functioning of neurons, oxidization of cells and inflammation in the brain. The known protective effects on inflammation and vascular function may contribute to better cognition in older adults and help delay the onset of Alzheimer's disease.
DHA is particularly important to brain functioning since it makes up 9-12 percent of the brain by weight. Low levels are associated with impaired cognitive function and stunted neurological growth in children. It's also been linked with an increase in the severity of symptoms in diseases like multiple sclerosis and Parkinson's disease.
Omega-3s and Diet
Some restricted diets like veganism create obstacles to getting enough EPA and DHA from food sources. That's because a strictly plant-based diet will only provide ALA, and it's challenging to get enough of it for our bodies to convert it to the levels of EPA and DHA needed to sustain good health. Adding fish to a vegan or vegetarian diet (referred to as a pescatarian diet) is a modification that will provide enough of these essential fatty acids for body processes.
The problem with relying only on vegetable sources for essential fatty acids is that we're not always able to convert them to EPA and DHA. ALA fatty acids are primarily used by the body for energy. Also, the right nutritional components in food are needed to produce the other two long-chain fatty acids. If there's a deficiency in magnesium or zinc, or in vitamins B-3, B-6 or C, it's difficult for the body to convert ALA to EPA and DHA.
Besides monitoring the intake of vitamins and minerals, those who follow a vegan diet should be sure to include as much as possible of these foods in the diet:
- Brussels Sprouts
- Cauliflower
- Flaxseeds
- Tofu
- Walnuts
Best Ratio of Omega-6 to Omega-3 Intake
Omega-6 fatty acids are a lot more common in food sources, and research has indicated that ingesting more omega-6s than omega-3s can also inhibit the conversion of ALA. Lower ratios of omega-6 to omega-3 have been associated with better outcomes for cardiovascular disease, colorectal cancer, breast cancer, rheumatoid arthritis and asthma. In the United States, the ratio of omega-6 to omega-3 fatty acids from food is estimated to be somewhere between 8:1 and 20:1, but a healthy ratio is closer to 3:1.
Low intake of fish is one reason for this imbalance, along with a lack of nuts and seeds in the diet (peanuts don't count since they're legumes). Another factor is that most of the meat and dairy products available come from cattle that are given feed rather than allowed to graze on grass. This is the reason that grass-fed beef is a healthier alternative. Three ways to lower your omega-6 intake are: choosing the cooking oils lowest in them, reducing total fat intake, and avoiding fried foods (they're usually fried with oils rich in omega-6).
Fats Lowest in Omega-6 Fatty Acids
- Canola Oil
- Coconut Oil
- Flaxseed Oil
- Olive Oil
There are other oils low in omega-6 fatty acids that aren't optimal for health because of the high saturated fat content, including butterfat, lard and palm oil. Although coconut oil is also high in saturated fat, its healthy properties make it a good choice for cooking recipes over a low heat setting. Flaxseed oil should be used as a salad dressing and in other cold prepared foods since heat greatly reduces its health benefits.
Top 15 Non-Fish Sources of Omega-3
- Black beans
- Canola oil
- Chia seeds
- Eggs
- Flax Seed
- Grass-fed beef
- Hemp Seed
- Kale
- Navy Beans
- Organic Milk
- Soybeans
- Spinach
- Walnuts
- Winter Squash
- Wild rice
Supplementing with Omega-3
Some concerns have been raised about the quality and safety of fish oil supplements because of PCB and mercury contamination in fish. These impurities tend to show up in muscle tissue, however, and they aren't as concentrated in the fatty parts of the fish. Independent studies from various laboratories in the U.S. have also shown these fears to be exaggerated.
Several independent laboratory analyses in the US have found commercially available omega-3 fatty acid supplements to be free of methylmercury, PCBs, and dioxins.
However, borage oil has been found to sometimes contain pyrrolizidine alkaloids that may be toxic and carcinogenic. Only borage oil that's certified as free of these alkaloids is considered safe to take as an ALA supplement. People who are taking chlorpromazine and other phenothiazines should avoid it altogether, along with evening primrose oil. In addition, anyone who is taking anti-coagulant medicine should check with their physician before supplementing with omega-3 fatty acids.
Cover All Your Nutritional Bases
We know that the omega-3 fatty acids ALA, DHA, AND EPA are all vital for good health. The surest way to get enough of all three is to follow a diet that includes plant, fish and meat sources of these healthy substances. Eating foods that enhance the amount of omega-3 fatty acids while getting sufficient amounts of omega-6 will also help protect your heart and brain. These essential fatty acids provide protection against inflammation and disease, so be sure and make them a cornerstone of your healthy eating plan.