You may not have given a lot of thought to omega fatty acids before, but there's a good chance you’ve heard of them. They’ve been in the news a lot lately, due to the fact they are in a lot of foods and are also available in dietary supplements. They’re even present in prescription drugs. But what are they and why are they so important to your health? Let’s take a look.
What are omega fatty acids?
Fish oil supplements are also used to treat some health conditions, like rheumatoid arthritis and high blood pressure as well as lowering triglyceride levels (2).
Are the benefits of Omega-3 supported by science?
Research shows that Omega-3 may help lower the risk of heart disease, stroke, and arthritis. Omega-3 is also used to treat high triglycerides, depression, ADHD, Alzheimer's disease, and ADHD (3).
Where to Get the Best Sources of Omega-3s?
This table lists common fish and seafood products and their omega-3 fatty acid content.
Type of Seafood
Omega-3 Fatty Acids (mg/serving)
Fish sticks (frozen)
Type of Seafood
Omega-3 Fatty Acids (mg/serving)
Tuna (light, skipjack)
SOURCE: Mozaffarian D, Rimm EB. JAMA. 2006;296:1885-1899.
Most people think of fish as the primary source of omega-3s, but there are many fishy alternatives to consider that contain the same nutrients. Here are some of the best food sources of omega-3s to consider.
If you're on a vegetarian or plant-based diet then alternative sources of Omega-3 such as seaweed and algae will be good sources to consume.
Seaweed, nori, spirulina, and chlorella are just some of the types that people eat for their health benefits.
Different ways to prepare it with other foods include:
Omega-3s are widely available in the plant kingdom, including in the fruit of the avocado. Avocados are high in fiber and contain no saturated fat. Studies have shown that the health benefit of avocados can also help lower LDL or “bad” cholesterol levels.
These contain high levels of Alpha-linolenic acid(ALA), as much as 5.055g/oz.
You can mix it in granola, smoothies, yogurt, or make chia seed pudding.
Research suggests that hemp seeds are good for a person’s heart, digestion, and skin.
Hemp makes an excellent addition to smoothies, granola, oats, and salads since it is slightly sweet. You can normally buy these at health shops or online.
Flaxseeds contain many nutrients that are beneficial to health. Studies have shown a correlation between the consumption of flaxseeds and a reduction in blood pressure and cardiovascular health(4).
Flaxseeds can be combined with oats and other cereals, or used in a smoothy by using flaxseed oil.
Walnuts are loaded with healthy fats, including ALA. Walnuts can be eaten on their own or used in trail mix, granola, yogurt, salads, and cooked dishes.
Edamame beans are immature soybeans and contain omega-3 and are high in plant-based protein, making it a great source of protein for vegetarians, vegans, and individuals on a plant-based diet.
Kidney beans work well in salads and stews and are a great source of fiber and omega-3.
Soybean oil contains about 0.923g/tbsp and is also a great source of riboflavin, magnesium, potassium, folate, and vitamin K. It can be used as an alternative to canola and sunflower oil in cooking.
Are fish oil capsules good for health?
Fish oil is a supplement that is usually taken by people who want to manage their fat levels. It is an oil that is made from fatty fish and is a rich source of omega-3 fatty acids. It is thought that taking this oil can help you to have a healthy heart and lower your risk of getting heart disease.
These days, you’ll find fish oil capsules everywhere—at your local grocery store, in drugstore aisles, and online. But are these supplements really good for you?
The problem with taking fish oil is that not all brands are as effective as others. Some people have side effects when taking it such as bad breath, gas, upset stomach, and even rashes. Some people are disappointed to find that it doesn't give them the changes to their blood triglyceride levels that they were hoping for (lowering LDL(a.k.a. bad) cholesterol and increasing HDL(a.k.a. good) cholesterol.
If you can find a reputable brand or product then there should be no problems or adverse side effects. A reputable brand will not give that bad fish taste in your mouth hours after you ingested it or upset your stomach and give you gas. Look for reputable brands here
Can chia seeds and flax seeds be eaten together?
Chia seeds (Salvia hispanica) and flax seeds (Linum usitatissimum) are two superfoods that are increasingly common in many diets, and for good reason. Both are high in important nutrients and are incredibly healthy and beneficial, both on their own and when combined.
The seeds are both high in fiber and aid digestive health. Chia seeds are rich in magnesium, a mineral that plays a role in regulating blood pressure and muscle contraction, along with calcium, copper, and manganese. They also contain thiamine, vitamin B6, phosphorous, zinc, and potassium.
Flax seeds are also rich in magnesium, as well as in manganese, boron, copper, iron, and vitamins B1 and B3. They have more protein than chia seeds, and the balance of amino acids in them makes them a good vegetarian source of protein.
They can be eaten together, but because they are so similar in the context of the nutritional benefits they provide, try not to take in too much of each on a daily basis, since the overconsumption of certain nutrients can lead to other adverse side-effects on your health.
Our recommendation would be to switch between the two on a regular basis. That way you won't exceed your daily allowances on certain vitamins and minerals and you get some variety to your diet on a regular basis.
What side effects can fish oil cause?
Fish oil is made from the fat of oily fish like sardines and salmon. It is high in omega-3 fatty acids, which have a number of health benefits which we discussed previously in this article. However, some people experience negative side effects when taking too much fish oil.
These side effects are:
Some studies have shown that supplementing with large amounts of omega-3 fatty acids could increase blood sugar levels in individuals with type-2 diabetes.
For example, one study found that a daily intake of 8 grams of omega-3 fatty acids increased blood glucose levels by 22% in people with type-2 diabetes over an eight-week period (5).
The reason cited is that large doses of omega-3s can stimulate the production of glucose, which in the long term can contribute to high levels blood sugar levels (6).
However, other research studies have turned up conflicting results, suggesting that only very high doses impact blood sugar.
Another analysis of 20 studies found that daily doses of up to 3.9 grams of EPA and 3.7 grams of DHA did not affect blood sugar levels for individuals with type 2 diabetes (7).
Excess fish oil consumption has been associated with nosebleeds and bleeding gums.
One study of 56 people found that healthy adults, supplementing with 640 mg of fish oil per day over a four-week period decreased blood clotting (8).
Another study showed that there's a higher risk of nosebleeds in adolescents that took between 1 and 5 grams of fish oil daily (9).
For this reason, it’s often advised to speak to your doctor before taking supplements, especially if you’re on blood thinners like Warfarin, and to stop taking fish oil prior to surgery.
Fish oil’s capacity to lower blood pressure is well documented.
One study of 90 people on dialysis found a significant decrease in both systolic and diastolic blood pressure when taking 3 grams of omega-3 fatty acids per day compared to a placebo (10).
A similar analysis of 31 studies concluded that those with high blood pressure or high cholesterol levels can effectively lower blood pressure when consuming fish oil (11).
While those with high blood pressure can reap the benefits of this, it can lead to serious problems for those with low blood pressure. If you're already on blood pressure-lowering medication it is advised to speak to your doctor before taking any additional fish oil supplementation.
One of the most common side effects of supplementing with fish oil is diarrhea and flatulence, especially in high doses (12).
Other types of omega-3 supplements such as flaxseed oil have also been found to have a laxative effect and may increase the frequency of an individual's bowel movement (13).
If you experience diarrhea after taking omega-3 fatty acids, make sure you’re taking your supplements with meals and consider decreasing your dosage to see if symptoms persist.
It is well documented that fish oil is beneficial for heart health, but some people reported that they get heartburn, belching, nausea, and stomach discomfort when taking fish oil supplements. Even though fish oil a healthy fat, fat, in general, has been shown to trigger ingestion (14)(15).
Sticking to a moderate dose and taking supplements with meals can often effectively reduce acid reflux and relieve symptoms.
Additionally, splitting your dose into a few smaller portions throughout the day may also help alleviate indigestion.
Hemorrhagic stroke or bleeding in the brain is usually caused when weakened blood vessels rupture. Some animal studies have found that blood’s ability to clot is decreased on a high intake of omega-3 fatty acids and increases the risk of hemorrhagic stroke (16)(17).
It is important to note that other studies have reported that there is no association between fish, fish oil intake, and the risk of getting a hemorrhagic stroke (18)(19).
It is advised to stay within the recommended daily amounts when consuming and supplementing with fish oil, and not overdo it. Also, speak to your doctor if you have any concerns or think that you might be a candidate for hemorrhagic stroke.
Certain types of omega-3 fatty acid supplements, such as cod liver oil are high in vitamin A, and can be toxic when consumed in large amounts. Just one tablespoon (14 grams) of cod liver oil can provide up to 270% of the daily vitamin A requirements (20).
Side effects such as dizziness, nausea, joint pain, and skin irritation have been associated with vitamin A toxicity (21).
Long term, it could also lead to liver damage and even liver failure in severe cases (22).
For this reason, it’s best to pay close attention to the vitamin A content of your omega-3 supplement and keep your dosage moderate.
Certain studies have found that fish oil in moderate doses of fish oil at 600mg/day for 16 weeks could improve the quality of sleep in children (23).
Other studies have found that high doses of fish oil worsened symptoms of insomnia and anxiety in people suffering from depression (24).
It is important to note that the research on the effects of fish oil and sleep are limited and that a lot of reports are anecdotal. So take the findings with a grain of salt and see for yourself how well you sleep when taking any fish oil supplement.
We would always recommend you keep a moderate approach to any form of supplementation and consult with your doctor if you are uncertain.
Should I be concerned about mercury in fish?
Mercury, a heavy metal found naturally in air, water, and soil can be released into the environment through industrial processes like the burning of coal or natural events like volcanic eruptions.
It’s released into the environment in several ways, including through industrial processes like burning coal or natural events like eruptions.
There are three main forms of mercury: (1) elemental or metallic, (2) inorganic, and (3) organic (25).
Fish such as shellfish can absorb low amounts of mercury due to water pollution. Methylmercury, the organic form of mercury can build up in their bodies over time. Methylmercury is highly toxic when it reaches high enough levels in the human body.
Many studies have determined that people who eat fish regularly have higher levels of mercury (26)(27).
Mercury in fish does not affect everyone in the same way. Therefore, certain people should take extra care.
People that are at risk include pregnant women, breastfeeding mothers, and young children.
Fetuses and children are more vulnerable to mercury toxicity, and mercury can easily be passed to a pregnant mother’s fetus or a breastfeeding mother’s infant. Children that have been exposed to methylmercury in the womb can struggle with attention, memory, language, and motor function (28)(29).
Overall, most people should not be worried about eating fish. The FDA recommends 2 to 3 servings of fish/week. Choose fish with low concentrations of mercury such as salmon, shrimp, sardines, and cod (30).
The only populations that are most a risk such as pregnant women, breastfeeding mothers, and young children should take extra care when consuming fish.
How much omega 3 should I be getting?
A minimum of 250–500 mg/day of combined EPA and DHA for healthy adults is recommended (31)(32)(33).
The recommended dietary allowance (RDA) for alpha-linolenic acid is 1.6 grams per day for men and 1.1 grams per day for women.
However, certain health conditions can require that you take in more or less omega-3 fish oil than that recommended for healthy adults (34).
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