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Fish Oils Hated By Docs!

I receive a monthly newsletter called “Diabetes Self Management” that gives little easy to digest research updates about diabetes and diabetic care. In it they recently discussed how fish oil supplementation “can actually worsen blood sugar control and increase insulin resistance in the body’s cells”.

For some reason the search engine is not working for me right now, so I can’t check any previous threads.

I’ve checked Med-line and found research discussing anti-inflammatory effects of fish-oil supplementation, but nothing relating to this subject.

Does anyone here know if they are blowing something out of proportion and applying this to diabetes, or this is a legitimate risk for diabetics?

We need a resident nutrition guru–ASAP! This is a very important question to a lot of us here.


My mother is a certified dietician and nutritionist (im 19 by the way), not to mention the head of the health department in northern virginia, i take fish oil sups for the intense stress i put on my joints, so i asked her about this, she did some research and asked her collegeues and came up with this conclusion…

  1. first off there was hardly any information specifcally on fish oil suppliments in terms of its relation to blood sugar and/or insulin therefore…

  2. she had a hard time making a connection between the types of oils (omega 3’s etc…) used in fish oils and any relation they might have to altering blood sugar levels and insulin levels (there was a whole bunch of nutritional mumbo jumbo in there and i apologize for not rememebering any of it over the phone)

  3. like aspirin once was, fish oil is in that stage of use where it’s benifeits are proven but not as widely accepted, yet. She would rather that have been published in a medical journal then a diabetes monthly newsletter which is probably funded by a healthcare system (such as an HMO, drug company) who recognizes a cost effective alternative when they see one. In short, she hasnt come across anything solid that would agree with their statement.

Then again, she isn’t exactly on the cutting edge research of fish oil supplements, so there could be new information out that she doesnt know about. Don’t take my post as a gospel, but i for one am still going to take my fish oil supps.


There has been suggestions that fish oils might be problematic for diabetes for ages. This has not been my experience, and I’ve worked with several diabetics all who did well taking fish oil.


subscription required:

In patients with diabetes or impaired glucose tolerance, fish oil doses greater than 3 grams per day might worsen glycemia (10007).

Kris-Ehterton PM, Harris WS, Appel LJ, et al. Fish consumption, fish oil, omega-3 fatty acids, and cardiovascular disease. Circulation 2002;106:2747-57.

However also please note their general comments on fish oil:

Orally, fish oils are generally well-tolerated at doses of 3 grams or less per day…

Doses greater than 3 grams per day of fish oil or high dietary intake of fish can inhibit platelet aggregation, cause bleeding, and potentially increase the risk for hemorrhagic stroke (1313,8699).

There’s also some evidence that fish oils in doses greater than 3 grams per day might adversely affect immune function. Fish oils appear to suppress T- and B-cell function and to reduce the production of cytokines, which might be detrimental to elderly people and people with suppressed immune function such as patients with human immunodeficiency virus (HIV) infection (1313,7383,7384).

Guys, this is some excellent information here. I’ll pass this on to my exercise science professor. (she wasn’t sure either)

If anybody else has any info, please lemme know. The dose-dependent glycemia was especially helpful!

now is it fish oil or the efa’s in the fish oil. maybe it is better to just injest the efa’s rather then all of the fish oil. They have recommended more then 3 grams of fish oil per day here at T-mag. anyone else have any idea? laters pk

[quote]pkradgreek wrote:
now is it fish oil or the efa’s in the fish oil. maybe it is better to just injest the efa’s rather then all of the fish oil. They have recommended more then 3 grams of fish oil per day here at T-mag. anyone else have any idea? laters pk[/quote]

Well EPA/DHA isn’t really considered as EFA. ALA found in flax oil is EFA. We can make our own EPA/DHA but not that much obviously. Our body needs ALA to convert to EPA/DHA but it varies greatly person to person. In diabetic (Type II) people, I don’t think they can convert ALA to EPA/DHA very well. I’m guessing in a moderate amount of EPA/DHA supplement (not to be confused with fish oil because some of the brands are really worthless crap due to low epa/dha content per gram) will help alot. It’s all about moderation, guys. I have no idea about the ‘effective’ dosage for epa/dha since everyone says different amount. Apparently in this case, the more is not necessarly better like other supplements.

Well, like mentioned above, the body’s capacity to make EPA/DHA from ALA varies greatly. Having said that, JB recommends 6-10 grams of EPA/DHA per day.

Any thoughts?

This really sounds off base.

LL is the good fat guru. Maybe he will stop by.

My fault, a better reference is:


Conflicting results have been reported regarding the effects of EPA supplements on glycemic control in non-diabetics with glucose intolerance, and those with type 2 diabetes. Some early studies indicated that EPA supplements might have detrimental effects in those groups. Recent, better designed studies have not reported these adverse effects. There is no evidence that EPA supplements have detrimental effects on glucose tolerance, insulin secretion or insulin resistance in non-diabetic subjects.

The usual oral dose of fish oil for use in hypertriglyceridemia is about 5 grams of combined EPA/DHA daily. The usual dose for hypertensives who have not previously been treated is about 3 grams of EPA/DHA daily. About 3 grams daily is also the usual dose for those with rheumatoid arthritis, Crohn’s disease and ulcerative colitis. Those who have had successful angioplasty and are trying to prevent restenosis might use 4 to 5 grams daily. Based on the GISSI-Prevenzione trial, a dose of 1 gram daily of EPA and DHA might have protective value for those who have had an MI