T Nation

Fish Oil


Since reading about the benefits of fish oil, I've been taking them religiously. I have some questions concerns I hope the more knowledgeable ones here can answer:

1) JMB says to shoot for 6g EPA/DHA a day. That is usually 20g of fish oil. Is that the upper limit, lower limit or somewhere in the middle?

2) Can you take too much fish oil?

I noticed that my blood pressure went from slightly above normal (normal=120/80) to slightly below that after starting taking fish oil. I sometimes get heart palpitations/arthymia when I consistatntly take 20g a few days in a row.

3) What about all those CAPS?

That's a lot of it! I put one cap in a glass of water once and once the oil is out, the remaining cap is pretty significant. Imagine taking 20 of tose a day! The label doen't list anything other than the oil but doesn't that contribute carbs/calories to your diet?


20 capsules are hard to get use to taking each day. Personally I buy a concentrated form from Wal-Mart. It has 40% more epa/dha so I only need to take 13 capsules instead of 20. Netrition sells a "pharmaceutical grade" fish oil that is 3 times as strong, so you only need to take about 7 a day.

Fish oil does have a blood thinning property, but you also need to be aware of what else you are taking. Aspirin? A lot of vit. E? Any medications? There are a lot of things that can thin your blood, and fish oil might just push you over the top.

I would not be worried about low blood pressure unless it is extremely low. I heard they were thinking of reducing normal from 120/80. But I should not comment on heart problems. Anyone else more experienced about this?



I don't know enough about the heart problem, but that definitely is not normal. I've never heard about getting too much fish oil other than getting too much polyunsaturated fat is not a good thing for long term health (should be under 5% of calories).

I don't like the idea of taking that many caps, either. Could you get the liquid form? It's cheaper, and I've never experienced bad burps like many people say they get (I have no idea why fish oil would make them burp). There is one issue with the liquid form...it tend to go rancid easier because once you open it, it's exposed to air. Gel caps are all sealed, so this isn't as much of an issue. Cod liver oil, however, resists going rancid because of the antioxidant vitamins in it. This is one reason I think cod liver oil is superior to normal fish oil. Not to mention most diets are low in vitamins A and D.

The gel cap is probably cellulose and/or gelatin, plus other possible binders and junk. That won't be contributing much, but it probably isn't great for you.

I wish I could have answered your questions better, but I hope this helps.



Yeah you can take too much of it and 6-10 grams EPA/DHA is the high end from what i've seen. Quite a few studies I've seen show the same type of effectiveness at 3 grams EPA/DHA per day. Fish oil is a blood thinner, much like aspirin or any pain reliever....You may want to taper the dosage back a bit.


Thanks all for your input.

The issue with the more concentrated form or the liquid form is the cost ratio (concentrated) and taste (liquid).
I'm used to and have no problem taking 20 a day. I'm just concerned that it is too much.

Thanks Kelly for ponting out that it is the upper limit. That was crucial.

Mage, I don't take aspirin or a lot of vitamin E. Just what's in my multi (and I only take 1/2 seving a day). So, I think it's just the fish oil that is causing this.

Thanks a lot NielG. I think the fish burps that everyone is talking about is due to the caps expanding in the stomach.

Why doesn't gelatin have any carbs/calories?

In light of all this information, I'm going to scale down to 10 day.

Why is more than 5% poly bad for the health?

If one should put a limit on fish oil and other ploys, on a low carb diet, how many percent of the total fat should come from them?


Kelly, a few questions about your post.

"Yeah you can take too much of it and 6-10 grams EPA/DHA is the high end from what i've seen."

What's your reference for the statement that you can take too much of it? I don't believe I've ever heard that stated before.

"Quite a few studies I've seen show the same type of effectiveness at 3 grams EPA/DHA per day."

Effectiveness at what? There are a myriad of things that essential fatty acids do in the body.

"Fish oil is a blood thinner, much like aspirin or any pain reliever...."

Most pain reliever don't "thin" the blood. The term is a misnomer in the first place, as no "thinning" takes place at all, but the blood becomes less coaguable. I'm not sure how this applies to his question at all or his "symptoms".


Gelatin is just protein, and cellulose won't be digested. How many calories from the capsule depend on how much of each is used. But I doubt adding maybe a couple grams of protein would really matter. So I shouldn't have said it doesn't have any calories.

I've tried to post links about the subject of fats before, but for some reason they didn't get posted. I'll just cut and paste an exerpt from one source (lemme know if you want the source, I can PM it to you):

"The dangers of polyunsaturates

The public has been fed a great deal of misinformation about the relative virtues of saturated fats versus polyunsaturated oils. Politically correct dietary gurus tell us that the polyunsaturated oils are good for us and that the saturated fats cause cancer and heart disease. The result is that fundamental changes have occurred in the Western diet. At the turn of the century, most of the fatty acids in the diet were either saturated or monounsaturated, primarily from butter, lard, tallows, coconut oil and small amounts of olive oil. Today most of the fats in the diet are polyunsaturated from vegetable oils derived mostly from soy, as well as from corn, safflower and canola.

Modern diets can contain as much as 30% of calories as polyunsaturated oils, but scientific research indicates that this amount is far too high. The best evidence indicates that our intake of polyunsaturates should not be much greater than 4% of the caloric total, in approximate proportions of 1 1/2 % omega-3 linolenic acid and 2 1/2 % omega-6 linoleic acid.30 EFA consumption in this range is found in native populations in temperate and tropical regions whose intake of polyunsaturated oils comes from the small amounts found in legumes, grains, nuts, green vegetables, fish, olive oil and animal fats but not from commercial vegetable oils.

Excess consumption of polyunsaturated oils has been shown to contribute to a large number of disease conditions including increased cancer and heart disease; immune system dysfunction; damage to the liver, reproductive organs and lungs; digestive disorders; depressed learning ability; impaired growth; and weight gain.31

One reason the polyunsaturates cause so many health problems is that they tend to become oxidized or rancid when subjected to heat, oxygen and moisture as in cooking and processing. Rancid oils are characterized by free radicals?that is, single atoms or clusters with an unpaired electron in an outer orbit. These compounds are extremely reactive chemically. They have been characterized as "marauders" in the body for they attack cell membranes and red blood cells and cause damage in DNA/RNA strands, thus triggering mutations in tissue, blood vessels and skin. Free radical damage to the skin causes wrinkles and premature aging; free radical damage to the tissues and organs sets the stage for tumors; free radical damage in the blood vessels initiates the buildup of plaque. Is it any wonder that tests and studies have repeatedly shown a high correlation between cancer and heart disease with the consumption of polyunsaturates?32 New evidence links exposure to free radicals with premature aging, with autoimmune diseases such as arthritis and with Parkinson's disease, Lou Gehrig?s disease, Alzheimer's and cataracts.33"

"If one should put a limit on fish oil and other ploys, on a low carb diet, how many percent of the total fat should come from them?"

It should still be under 5%. The reaon why you would still want to supplement with fish oils (especially cod liver oil) is that they have so much good to offer that it far outweighs any bad. And the vitamins in cod liver oil help prevent the oxidation, making it "safer" than normal fish oil. That is another reason I highly recommend CLO over normal fish oil.

Hope this helps,


So if fish oil should only make up 5% of a persons total calories, what makes up the other 25% fat of someone eating a 30% fat diet? Flax oil? Nuts? Saturated fat? If a diet should contain no more than 10% sat. and 5% poly, the other 10-15% would have to come from mono's and wouldn't that throw off the omega 3-omega 6 ratio? It just doesn't add up. I would like to hear JB's response to that post.


Hmmm. That definitely puts a spin on things. Now even the "good" fats are bad.

But the article does say that it is only bad if it gets rancid or oxidated.
I'm sure that all the touted benefits of polys and that we are still eating too much saturated fat and that it is bad still holds?

So in your opinion, on a low carb diet, or any diest for that matter - 5% polys, how much monos and how much saturated fats?


Taking too much I guess it's up to the individual. For the past 2 years I've recommended 6-10 g DHA/EPA but after further exploration I now am a bit more conservative and recommend around 3 grams combined. From what I've seen I don't think more is necessarily better above a certain point when it comes to fish oil. Fish oil lowers Arichidonic acid and that may not necessarily be a good for muscle growth. It may have a negative effect on androgen levels at high doses and does effect coagulation and bleeding time:

In this study 4 g EPA increased bleeding time by by 57% and the threshold dose of collagen needed to induce platelet aggregation by 46%. I guess that's not necessarily a bad thing but does show it's some pretty powerful stuff. Biochim Biophys Acta 1991 Jan 4;1081(1):33-8
Eicosapentaenoic acid ethyl ester as an antithrombotic agent: comparison to an extract of fish oil.
Wojenski CM, Silver MJ, Walker J.

Here's a couple that show the possible negatives on androgens in men:
Relationships between types of fat consumed and serum estrogen and androgen concentrations in Japanese men.

Nagata C, Takatsuka N, Kawakami N, Shimizu H.

Department of Public Health, Gifu University School of Medicine, Japan.

The relationships between types of fat consumed and serum concentrations of estrone, estradiol, total and free testosterone, dihydrotestosterone, and sex hormone-binding globulin were examined in 69 Japanese men aged 43-88 years. Diet was assessed by a semiquantitative food frequency questionnaire. Intake of saturated, monounsaturated, and polyunsaturated fats was inversely correlated with serum total testosterone after controlling for age, total energy, body mass index, alcohol intake, and smoking status, but the correlation was statistically significant only for polyunsaturated fat (r = -0.29, p = 0.02). Intakes of eicosapentanoic and docosahexaenoic acids, n-3 fatty acids from fish, were significantly inversely correlated with total testosterone (r = -0.25, p = 0.04 and r = -0.32, p = 0.01, respectively). Serum estrone, estradiol, and free testosterone were not significantly correlated with any type of fat studied. The correlations of total testosterone with n-3 fatty acids from fish remained significant after additional adjustment for the other categories of fat (r = -0.27, p = 0. 03 for eicosapentanoic acid and r = -0.32, p = 0.01 for docosahexaenoic acid), while the correlations with saturated and monounsaturated fats became nearly null after the adjustment.

Steroid Biochem 1984 Jan;20(1):459-64 Related Articles, Links

Diet and serum sex hormones in healthy men.

Hamalainen E, Adlercreutz H, Puska P, Pietinen P.

The possible effect of dietary fat content and the ratio of polyunsaturated to saturated fatty acids (P/S-ratio) on serum sex hormones was studied in 30 healthy male volunteers. The customary diet of the subjects, which supplied 40% of energy as fat (mainly from animal sources, P/S-ratio 0.15) was replaced for a 6 weeks period by a practically isocaloric experimental diet containing significantly less fat (25% of energy) with a higher P/S-ratio (1.22) and other environmental factors were stabilized. Serum testosterone and 4-androstenedione decreased from 22.7 +/- 1.1 nmol/l to 19.3 +/- 1.2 nmol/l, (SEM, P less than 0.001) and from 4.6 +/- 0.2 nmol/l to 4.3 +/- 0.2 nmol/l (SEM, P less than 0.01), respectively. These changes were paralleled by a reduction in serum free (non-protein bound) testosterone (P less than 0.01) suggesting a possible change in biological activity. During the low fat period a significant negative correlation between serum prolactin and androgens was observed. All the changes in androgen levels were reversible. With the exception of a small but non-significant decrease in serum estradiol-17 beta, the other hormone parameters were practically unaffected by the dietary manipulation. Our results indicate that in men a decrease in dietary fat content and an increase in the degree of unsaturation of fatty acids reduces the serum concentrations of androstenedione, testosterone and free testosterone. The mechanism and importance of this phenomenon is discussed in the light of epidemiological and experimental data.

and this study that showed hyperglycemia although it was in diabetic patients

The majority of studies showing beneficial effects, which are usually regarding treatment of specific conditions, have used 1-2 g. From what I've seen there is little added benefit with >3-4 g. And 1-2 g gets most of what we're looking for, at the very least. The beneficial effects as I seem them were summed up very nicely by Eric Cressey a couple of weeks ago. Insulin sensitivity, depression, inflammation etc.

Here's one study that Berardi wrote about that actually used 6 grams total fish oil or only 1.8 grams EPA/DHA that still had a profound effect.
During an OGTT (oral glucose tolerance test) the fish oil group burned 27g of fat vs. 20g in the placebo group. The fish oil group also burned 28g or carbs while storing 36g and the placebo group burned 51g of carbs while storing only 14g.

In addition, baseline insulin was 30% lower in fish oil group and insulin responses to OGTT were 50% lower in the fish oil group. What this tells us is that fish oil allows the body to burn more fat and store more muscle glycogen, repartitioning fuel away from fat cells toward muscle cells.

Effects of fish oil on metabolic responses to oral fructose and glucose loads in healthy humans.

Delarue J, Couet C, Cohen R, Brechot JF, Antoine JM, Lamisse F.

Laboratoire de Nutrition et Jeune Equipe 313 Lipides et Croissance, Universite de Tours, France.

This study examines the effect of the substitution of 6 g/day of fish oil in a saturated diet on glucose and fructose metabolism in healthy humans. Five subjects were submitted to two 3-wk controlled-diet periods (polyunsaturated/saturated = 0.21). During one period, 6 g/day of fat used for dressing were replaced by 6 g/day of fish oil [1.1 g/day of 20:5 (n-3) fatty acids and 0.7 g/day of 22:6 (n-3) fatty acids]. At the end of each period the subjects ingested a 1 g/kg fructose or glucose load 2 days apart. Plasma glucose fluxes were traced with the use of deuterated glucose and [U-13C]glucose. Substrate oxidation was measured by indirect calorimetry. Fish oil induced a 4% increase in basal and postload glycemia and a 40% decrease in insulinemia, whereas plasma C-peptide remained unaffected. Glucose fluxes were unaffected by fish oil, but carbohydrate (CHO) oxidation was reduced (fructose: 55.5 +/- 4.1 vs. 62.9 +/- 3.6 g/6 h; glucose: 36.7 +/- 4.7 vs. 50.5 +/- 4.7 g/6 h; all P < 0.05). Lipid oxidation was increased 35% by fish oil after both CHO loads. Nonoxidative glucose disposal was increased by fish oil (fructose: 9.4 +/- 2.5 vs. 2.9 +/- 1.1 g/6 h; glucose: 28.3 +/- 5.1 vs. 14.4 +/- 4.7 g/6 h; all P < 0.05). Fish oil could affect glucose transport and decrease CHO oxidation through the decrease in insulinemia and/or a specific effect on glycolytic pathway.


This is a great thread. The fish oil supplement I use is a 1g softgel. it has 180mg of EPA and 120mg of DHA. So, for 3g combined, the recommendation would be to take about 10 of these per day? That would be 10g of fat, but only 3g of EPA/DHA combined. I take about 1 tbsp of flax on top of that.



Dang! Well, that should start up some interesting discussions here.

So - anecdotally - anyone here start taking a lot of fish oil and notice a decrease in libido or sexual performance? Inquiring minds wanna know...


Hey guys,

I definitely have an answer. The rest of the fat, if only less than 5% is poly, should be monounsaturated and mostly saturated. Before you brush this off and think I'm a retard, please read this:

"The benefits of saturated fats

The much-maligned saturated fats?which Americans are trying to avoid?are not the cause of our modern diseases. In fact, they play many important roles in the body chemistry:

Saturated fatty acids constitute at least 50% of the cell membranes. They are what gives our cells necessary stiffness and integrity.

They play a vital role in the health of our bones. For calcium to be effectively incorporated into the skeletal structure, at least 50% of the dietary fats should be saturated.38

They lower Lp(a), a substance in the blood that indicates proneness to heart disease.39 They protect the liver from alcohol and other toxins, such as Tylenol.40

They enhance the immune system.41

They are needed for the proper utilization of essential fatty acids.
Elongated omega-3 fatty acids are better retained in the tissues when the diet is rich in saturated fats. 42

Saturated 18-carbon stearic acid and 16-carbon palmitic acid are the preferred foods for the heart, which is why the fat around the heart muscle is highly saturated.43 The heart draws on this reserve of fat in times of stress.

Short- and medium-chain saturated fatty acids have important antimicrobial properties. They protect us against harmful microorganisms in the digestive tract.

The scientific evidence, honestly evaluated, does not support the assertion that "artery-clogging" saturated fats cause heart disease.44 Actually, evaluation of the fat in artery clogs reveals that only about 26% is saturated. The rest is unsaturated, of which more than half is polyunsaturated.45 "

I'm trying to get this evidence out here that saturated fats are NOT bad for you in any way. If I can do this, then everyone would have more freedom with using a diet high in saturated fat to boost testosterone. If you think about it, this makes a ton of sense. Nature intended for us to eat high fat, because if we eat a diet high in saturated fat, our testosterone levels rise, which helped us survive!

Also, a higher intake of saturated fats could offset the possible reduction in T levels like Kelly mentioned. Not to mention if you eat NATURAL high fat animal products, you'll probably get more vitamins A and D, which are extremely important for growth and development. So the key above all is to eat natural fats, not these vegetable oils, and to supplement lightly with your choice of EFAs.

Here is a link on vitamin A:


Here's some info on cholesterol, too, since high cholesterol foods are usually high saturated fat foods, too:

"What about cholesterol?

And what about cholesterol? Here, too, the public has been misinformed. Our blood vessels can become damaged in a number of ways?through irritations caused by free radicals or viruses, or because they are structurally weak?and when this happens, the body?s natural healing substance steps in to repair the damage. That substance is cholesterol. Cholesterol is a high-molecular-weight alcohol that is manufactured in the liver and in most human cells. Like saturated fats, the cholesterol we make and consume plays many vital roles:

Along with saturated fats, cholesterol in the cell membrane gives our cells necessary stiffness and stability. When the diet contains an excess of polyunsaturated fatty acids, these replace saturated fatty acids in the cell membrane, so that the cell walls actually become flabby. When this happens, cholesterol from the blood is "driven" into the tissues to give them structural integrity. This is why serum cholesterol levels may go down temporarily when we replace saturated fats with polyunsaturated oils in the diet.46

Cholesterol acts as a precursor to vital corticosteroids, hormones that help us deal with stress and protect the body against heart disease and cancer; and to the sex hormones like androgen, testosterone, estrogen and progesterone.

Cholesterol is a precursor to vitamin D, a very important fat-soluble vitamin needed for healthy bones and nervous system, proper growth, mineral metabolism, muscle tone, insulin production, reproduction and immune system function.

The bile salts are made from cholesterol. Bile is vital for digestion and assimilation of fats in the diet.

Recent research shows that cholesterol acts as an antioxidant.47 This is the likely explanation for the fact that cholesterol levels go up with age. As an antioxidant, cholesterol protects us against free radical damage that leads to heart disease and cancer.

Cholesterol is needed for proper function of serotonin receptors in the brain.48 Serotonin is the body's natural "feel-good" chemical. Low cholesterol levels have been linked to aggressive and violent behavior, depression and suicidal tendencies.

Mother's milk is especially rich in cholesterol and contains a special enzyme that helps the baby utilize this nutrient. Babies and children need cholesterol-rich foods throughout their growing years to ensure proper development of the brain and nervous system.

Dietary cholesterol plays an important role in maintaining the health of the intestinal wall.49 This is why low-cholesterol vegetarian diets can lead to leaky gut syndrome and other intestinal disorders.
Cholesterol is not the cause of heart disease but rather a potent antioxidant weapon against free radicals in the blood, and a repair substance that helps heal arterial damage (although the arterial plaques themselves contain very little cholesterol.) However, like fats, cholesterol may be damaged by exposure to heat and oxygen. This damaged or oxidized cholesterol seems to promote both injury to the arterial cells as well as a pathological buildup of plaque in the arteries.50 Damaged cholesterol is found in powdered eggs, in powdered milk (added to reduced-fat milks to give them body) and in meats and fats that have been heated to high temperatures in frying and other high-temperature processes.

High serum cholesterol levels often indicate that the body needs cholesterol to protect itself from high levels of altered, free-radical-containing fats. Just as a large police force is needed in a locality where crime occurs frequently, so cholesterol is needed in a poorly nourished body to protect the individual from a tendency to heart disease and cancer. Blaming coronary heart disease on cholesterol is like blaming the police for murder and theft in a high crime area.

Poor thyroid function (hypothyroidism) will often result in high cholesterol levels. When thyroid function is poor, usually due to a diet high in sugar and low in usable iodine, fat-soluble vitamins and other nutrients, the body floods the blood with cholesterol as an adaptive and protective mechanism, providing a superabundance of materials needed to heal tissues and produce protective steroids. Hypothyroid individuals are particularly susceptible to infections, heart disease and cancer.51"



Thanks for the references, Kelly. Very interesting. I'm curious as to what JB would say about all of this.


Your quotes are great!

This helps to emphasize that fat is NOT the enemy and we should not try to completely eliminate it from our diets. It's okay to eat lean ground beef with some of the fat still in it, and eat butter, 2 % milk, pork chops and bacon. Fat is okay! In fact, I 've just been feeding pork chops, lard and bacon to my subjects in my research study for the past five months, and their blood cholesterol and CRP (a marker of inflammation) were actually improved from their habitual diets! I wish I could have measured thier T levels, but it was not part of the research focus. Anyways, the point is that saturated fat is NOT evil. The correlation between sat fat and chronic disease mostly comes from the foods that have hydrogentated sat fat which creates the trans fatty acids. TFA's are the most dangerous and will supress T!

And DocT, there is a level of fish oil that can be harmful. The omega-3 expert, Bruce Holub from the U of Guelph, has found that getting more than 3 grams a day of EPA and DHA from food and supplements combined may raise the risk of hemorrhagic stroke. So, if you take more than 20 caps a day of fish oil you can cause more harm than good. Also, it'll get tight on your pocketbook too!


This really doesn't mean squat but the maximum safe daily dosage recommended by the United States food and drug administration for a 70 kg human is a total of 3 g of combined EPA/DHA from conventional and dietary sources.

I just think people need to be aware of the positives as well as possible negatives. Personally, I would worry a bit about someone who was taking 10 g combined EPA/DHA who perhaps also used gingko biloba and ginseng (other anti-coagulants), as well as NSAIDS as a lot of people who train are apt to do.


Cass, anything that causes a decrease in coaguability is going to increase the risk for all kinds of hemorrhage. I haven't seen the actual numbers, but I doubt it's clinically significant in otherwise healthy people. If I'm horribly wrong, please correct me.

And 6g DHA/EPA per day isn't expensive if you shop around.


I should also add that the very factor that increases the risk of cerebral hemorrhage (the lowered coaguability) will DECREASE the risk of far more prevelant diseases, namely pulmonary embolus, myocardial infarction, deep vein thrombosis, and embolic strokes.

You just have to take information with a grain of salt and see it in the larger context as well.


Good topic. It's somthing I've been toying with nyself for a few months; that is trying to balance sat fat vs polys and monos.

Neil: I tend to agree with the articles you posted; I believe that was from Dr.s Mary Enig and Sally Fallon, was it not? They have been proponents of sat fat for years now. The cholesterol issue is a hot one too. Uffe Ravnskov Ph.D,MD has written a book called 'the cholesterol myths'. In it, he describes how the body produces about 400 times the amount of cholesterol that you eat in a day, so cholesterol rich foods are no problem. Cholesterol is the body's main steroid, and is produced to heal. Those with high cholesteroltend to be unhealthy and tht's the exact reason they have high cholesterol - because the body is making it to combat the state of ill health. This is also the reason that garlic helps 'high cholestrol' - b/c it has such helathful properties and helps restore the body's balance that the body doesn't need to produce as much cholesterol,. and therefore the level goes down.

One point I would like to make is that eating sat from feedlot beef and commercial eggs,chicken,and pork, ios probably not all that healthy b/c that's where all the shit that goes into them is stored. Most people can't afford to be buying grassfed organic meats, so I buy the leanest of them, and for sat fat I add coconut butter. It's clean of all the antibiotics, hormones etc, and it's nearly pure sat fat.


Great thread.

I naturally have low blood pressure, that is usually less than 95/60 and resting heart rate 48 bpm.

Although I feel heart palpitations and or light-brief dizziness, it only happens about once every 4 weeks or so.

I am wondering if fish or cod liver oil would kill me! I know the stuff is good, but I don't wanna die!!!

Thanks for your help.