We get asked about supplements all the time in the Sleekgeek Health Revolution Facebook Group, so I’ve put together this guide to explain things from our perspective here at Sleekgeek.

I hope that you find it helpful in cutting through all the hype and marketing that typically surrounds supplements so that you can get down to the real-world benefits and everyday use.

Feel free to jump right to the bottom for our specific brand recommendations – but please do read on for full context and insight.

A quick word on responsibility and doing your research: One of the best things you can do when it comes to supplements of any kind is to look them up on Examine.com.

They are a great resource for independent and unbiased information on supplementation and nutrition to help you cut through all of the hyped-up marketing and commercial interest out there so that you can focus on what really works and avoid wasting your money.

What is a fish oil supplement?

Fish oil, as the name suggests, is a supplement that contains oil extracted from fatty fish like sardines, anchovies, mackerel, and salmon.

We most commonly consume fish oil in the form of capsules, but they can also be consumed in liquid form.

You may also find it simply called an omega-3 supplement, but closer inspection of the label will tell you if it’s sourced from fish or other sources of omega-3s.

Fish oil provides a rich source of two important omega-3 fatty acids: EPA (eicosapentaenoic acid) and DHA (docosahexaenoic acid).

Omega-3 fatty acids are often considered to be the “anti-inflammatory” fatty acids, whereas omega-6- fatty acids are considered to be the more “pro-inflammatory” fatty acids.

Are fish oil supplements useful?

First off, no one needs a fish oil supplement.

But, as mentioned above, fish oil provides a rich source of the omega-3 fatty acids EPA and DHA.

We can’t make these omega-3 fatty acids in our bodies, so we need to get them from our diets. In fact, the World Health Organization (WHO) specifically recommends eating 1-2 portions of fatty fish per week in order to obtain these healthy fats.

However, most people don’t eat much fatty fish and omega-3 fatty acids are fairly hard to come by from any other food source.

Furthermore, our modern “Western Diets” are very rich in the more pro-inflammatory omega-6 fatty acids from processed foods and vegetable oils. We should ideally have a 1:1 ratio of omega-3 to omega-6 fatty acids, but the average ratio is currently around 1:15 or worse.

According to Precision Nutrition, “NIH researchers have said that the billions we spend on anti-inflammatory drugs such as aspirin, ibuprofen, and acetaminophen is money spent to undo the effects of too much omega-6 fat in the diet.”

Therefore, fish oil or omega-3 supplements are a very useful, convenient, and affordable way to obtain more omega-3 fatty acids in our diet.

What are the benefits?

Fish oil is perhaps one of the best general health supplements out there with a wide variety of benefits and a high amount of research.

Examine.com cite over 700 unique references in their research roundup on fish oil.

Some of the main benefits can be distilled as:

• Heart health – Fish oil can reduce some of the risks associated with heart disease. Studies have also shown that people who eat a lot of fish have much lower rates of heart disease.

• Mental disorders – Fish oil can reduce the risk of psychotic disorders and improve symptoms of certain psychiatric disorders. Studies have also shown that people with certain mental disorders typically have lower omega-3 blood levels.

• Depression and anxiety – Fish oil may improve the symptoms of depression and anxiety. Studies have also shown that people with major depression appear to have lower blood levels of omega-3s.

• Eye health – Fish oil may improve eye health and reduce age-related macular degeneration as well as risk for eye diseases. Omega-3 fatty acids are an important part of our eyes.

• Reduce inflammation – Fish oil has anti-inflammatory properties which can help to treat diseases that involve chronic inflammation (obesity, diabetes, depression, heart disease, and rheumatoid arthritis, for example).

• Skin health – Fish oil may benefit certain skin disorders, especially ones related to old age or too much sun, such as psoriasis and dermatitis.

• Attention and hyperactivity – Fish oil has been shown to improve perceived hyperactivity, inattention, impulsiveness, and aggression in children. 

• Asthma and allergies – Fish oil has been shown to reduce asthma symptoms as well as the risk of allergies  (in infants when supplemented by mothers during pregnancy).

There are also some benefits that omega-3 fatty acids can benefit brain health and intelligence, symptoms of metabolic syndrome, autoimmune diseases, Alzheimer’s Disease, cancer, liver fat, bone and joint health, menstrual pain, sleep, skin cells, and more – BUT it’s not clear whether these same benefits can be achieved directly from fish-oil or not.

What are the downsides?

Fish oil supplements seem to be remarkably safe, with the FDA setting a safe upper daily limit to 2,000mg of combined EPA and DHA (your fish oil will give those doses on the label).

However, there are some minor side effects to regular supplementation as well as some safety concerns around extremely high doses.

• Stimulatory effect – Fish oil is not a stimulant, but it can increase brain activity and may feel stimulating to those who are sensitive to it. Some studies have found that moderate doses of fish oil improves sleep quality, but another study found that taking too much fish oil interfered with sleep and contributed to insomnia. If in doubt, stick to the lower recommended doses on your product and take it in the morning with breakfast.

• Fish burps – Fish oil can indeed smell and taste fishy when the capsule dissolves. Usually, the capsules are designed to only dissolve once it reaches the small intestine but it doesn’t always work. Consuming your fish oil with food and keeping them cold in the fridge or freezer can help you avoid fish burps. Liquid fish oil supplements usually come with a strong flavour, like lemon, to help mask the smell and taste.

• They can go rancid – Fish oil can go rancid if expired or left exposed (you should keep yours in the fridge or freezer for maximum freshness and rather buy it in smaller batches than in bulk containers). The same capsule coating mentioned above which is designed to prevent fish oil from dissolving too soon can also mask the rancid smell. Ideally, cut a capsule open when you first get the product to check it’s freshness and get familiar with what fresh fish oil smells like (fishy), and then check periodically when you are halfway through the tub and again when you are nearing the end to make sure they don’t actually smell “off” (it will smell really weird or foul).

• Thins blood – Fish oil (or more specifically, the omega-3 fatty acids) can thin your blood. If you already struggle with this or are already on blood thinning medications, then you should consult with your doctor first (you should do this before taking ANY supplement, regardless of it’s claimed benefits and hype).

• Lowers blood pressure – Fish oil (or more specifically, the omega-3 fatty acids) may lower your blood pressure. If you already struggle with this or are already on blood pressure medications, then you should consult with your doctor first (you should do this before taking ANY supplement, regardless of it’s claimed benefits and hype).

• Diarrhea – Fish oil taken in extremely high doses (3 grams or more per day) can cause diarrhea. 

• Fish or seafood allergy – If you have a fish or seafood allergy then it’s possible that you may have an allergic reaction to fish oil. There isn’t much reliable information about this out there and it seems to be extremely uncommon (if even true at all), but I thought it would be worth mentioning it here just in case.

• Supplement, not a replacement – Many people mistakenly believe that taking a fish oil supplement can replace eating fish in their diet. It’s a supplement, not a replacement. Real food contains many other vitamins, minerals, fiber, nitrates, and phytochemicals that are not found in supplements and may be more effective when consumed in whole food form.

• Sustainability – Fish oil can come from a variety of sources. It’s worth looking into the company you use to make sure that they put an effort into sustainable practices. For example, some companies produce fish oil from leftover fish carcasses rather than whole fish. Other companies opt to make fish oil from smaller and more plentiful fish like anchovies and sardines as opposed to larger fish.

Sleekgeek’s Position:

Fish oil is a great general health supplement with a wide variety of benefits and a high amount of research.

The benefits to fish oil and improved omega-3 to omega-6 intake (especially around inflammation) are tangible and very closely linked to your overall success when it comes to weight loss, weight maintenance, and living a healthy, fit lifestyle.

We feel that if you do want to include supplements in your diet, then you are much better served by supplementing with fish oil than something like a “fat burner” or “detox clean pill”.

However, it’s definitely not a requirement for a healthy lifestyle.

If you want some specific and practical guidelines:

1) Eat more omega-3 rich foods.

The first rule of supplementing is that you should be making a conscious and consistent effort through your diet first. Supplements are in no way a replacement for a healthy diet.

Many people mistakenly believe that taking a fish oil supplement can replace eating fish in their diet. Real food contains many other vitamins, minerals, fiber, nitrates, and phytochemicals that are not found in supplements and may be more effective when consumed in whole food form.

Healthline has a great article listing 12 Foods That Are Very High in Omega-3.

According to them, great choices for getting more EPA and DHA omega-3s include:

• Mackerel (4,107 mg per serving)
• Salmon (4,023 mg per serving)
• Cod Liver Oil (2,644 mg per serving)
• Herring (3,181 mg per serving)
• Oysters (565 mg per serving)
• Sardines (2,205 mg per serving)
• Anchovies (951 mg per serving)
• Caviar (1,086 mg per serving)

And then the following foods provide another kind of omega-3 called ALA which is inferior to EPA and DHA, and needs to be converted (rather poorly) into EPA or DHA in order to be used:

• Flaxseeds (2,388 mg per serving)
• Chia Seeds (4,915 mg per serving)
• Walnuts (2,542 mg per serving)
• Soybeans (1,241 mg per serving)

Some other food sources that contain omega-3s, although not in such high amounts, include:

• Pastured eggs and omega-3-enriched eggs
• Meats and dairy products from grass-fed animals
• Hemp seeds
• Vegetables like spinach and Brussels sprouts.

2) Eat less omega-6 rich foods.

Much of the benefit from fish oil (and omega-3s) comes from improving your omega-3 to omega-6 ratio.

Omega-3 fatty acids are often considered to be “anti-inflammatory”, whereas omega-6- fatty acids are considered to be the more “pro-inflammatory”.

We can’t make omega-3 fatty acids in our bodies, so we need to get them from our diets. However, most people don’t eat much fatty fish and omega-3 fatty acids are fairly hard to come by from any other food source.

Furthermore, our modern “Western Diets” are very rich in the more pro-inflammatory omega-6 fatty acids from processed foods and vegetable oils. We should ideally have a 1:1 ratio of omega-3 to omega-6 fatty acids, but the average ratio is currently around 1:15 or worse.

Therefore, fish oil or omega-3 supplements are a very useful, convenient, and affordable way to obtain more omega-3 fatty acids in our diet.

But as we said in point #1 above: The first rule of supplementing is that you should be making a conscious and consistent effort through your diet first.

This means, eating less:

• Processed seed and vegetable oils that are high in omega-6 fatty acids.
• Processed foods that contain these seed and vegetable oils (which is pretty much most processed food).

This graphic from Healthline shows the fatty acid content in various oils, with the ones high in blue-coloured Linoleic Acid that you want to avoid:

This shows that:

• The oils highest in omega-6 fatty acids (that you want to avoid) are sunflower, corn, soybean, and cottonseed oils.
• The oils lowest in omega-6 fatty acids (that you might want to use instead)are butter, coconut oil, lard, palm oil, and olive oil.

3) Choose a good brand.

Quality, consistency in quality, freshness, dosage, and sustainability are always a concern when it comes to supplements.

When it comes to quality, not only does the quality of products vary dramatically from one brand to another, but the consistency of that quality can also differ over time.

A solution to this is to hedge your bet by identifying 2-3 brands that you trust or have been recommended and then rotate through them each time you need to replace your product.

For example, you might use Brand A for a month, and then use Brand B for the next month, and then Brand C for the next month before going back to Brand A again.

As for freshness, we cover this more in-depth below but it’s important to check the best-before date on the product. You should cut open a fish oil capsule when you first get the product to make sure it’s not rancid and then check periodically that the rest haven’t gone off. Keeping your fish oil in the fridge or freezer and reducing it’s exposure to air and sunlight will help keep it fresher for longer.

Dosage can vary from brand to brand, and the recommended dosage can also vary depending on what your goal with supplementing fish oil is in the first place.

Examine.com recommend between 250mg and 1,000mg of combined EPA and DHA as the minimum dose for general health. This seems to be pretty consistent with the recommendations from most other organizations.

According to Healthline, the FDA claims the safe upper limit is 3,000mg while the EFSA (European equivalent of the FDA) has declared up to 5,000mg per day from supplements safe.

WebMD also lists several studies and the dosages that they used for various goals ranging from heart disease to ADHD to dry eye to psoriasis.

My bet is with Precision Nutrition (the company who Sleekgeek works with for the Sleekgeek Coaching Program) and their recommendation of 3-9 grams of fish oil (about 1-3 grams of combined EPA and DHA) per day.

Finally, with sustainability, it’s worth looking into the company you use to make sure that they put an effort into sustainable practices. For example, some companies produce fish oil from leftover fish carcasses rather than whole fish. Other companies opt to make fish oil from smaller and more plentiful fish like anchovies and sardines as opposed to larger fish. Precision Nutrition also add that smaller fish are lower on the food chain and less likely to accumulate environmental toxins.

4) Keep it cold and covered.

As hinted at above in the previous point, as well as in one of the downsides to fish oil supplements: Fish oil can go rancid.

This means that you should keep it in the fridge or freezer for maximum freshness. This can also help prevent “fish burps” by helping the capsule to dissolve slower during digestion.

You should try to minimise your fish oil supplements exposure to air and sunlight as much as possible to prevent oxidation. So when you take it out of the fridge or freezer, don’t leave the container lying open and exposed while you take your supps. Close it and put it back in the fridge or freezer ASAP.

5) Check for rancidity.

As hinted at above in the previous 2 points, as well as in one of the downsides to fish oil supplements: Fish oil can go rancid.

Be sure to check the best before date when you buy your product.

Fish oil capsules are designed to only dissolve once it reaches the small intestine in order to hide the fishy taste and prevent “fish burps”. However, this same capsule can also mask the smell of rancid fish oil.

When you first get your product you should cut one of the capsules open to check it’s freshness and get familiar with what fresh fish oil smells like (fishy). You should check periodically when you are halfway through the tub and again when you are nearing the end (or if you haven’t used the supplement for a while) to make sure that they don’t actually smell “off” (it will smell really weird or foul).

You can also buy your fish oil in smaller batches rather than in bulk containers so that each batch is likely to be fresher and you will replace it sooner with a new fresh batch before it can go off.

6) Consume with food.

Consuming your fish oil with food (ideally breakfast) will improve it’s absorption (especially if the meal contains other healthy fats) and help to prevent “fish burps”.

On the topic of food, if you have a fish or seafood allergy then it’s possible that you may have an allergic reaction to fish oil too. There isn’t much reliable information about this out there and it seems to be extremely uncommon (if even true at all), but I thought it would be worth mentioning it here just in case.