Dear Doctor. Roach: I have a question about omega-3 fatty acid intake, either from eating fish or from supplements like fish oil.
Apparently, many American diets are omega-3 fatty acid deficient. One possible reason is that most American cattle are fed mostly corn rather than grass, resulting in low-omega-3 meat.
Most of the arguments in favor of increased omega-3 intake seem to be related to heart health. But omega-3 fatty acids are also important for brain health. Specifically, I wonder if there could be a link between these nutritionally low omega-3 levels and our dementia and Alzheimer’s epidemic. – AJS
Reply: Grass-fed beef contains more omega-3 oils than grain-fed beef. Compared to other sources, however, the amount is still relatively small, even for grass-fed beef. A standard serving of grass-fed beef fillet contains about 65 mg of omega-3 fats, about 50% more than grain-fed ones.
There is no “official” recommended intake for omega-3 fatty acids, but the Institute of Medicine found that healthy adults eat 1,100 (women) and 1,600 (men) per day.
Grass-fed beef isn’t really a good source to get there.
It would take 4.5 pounds of grass-fed beef daily to reach the men’s goal – not a healthy choice. A single serving of salmon is more than 1,800 mg.
More importantly, although the data remains mixed, most studies show that switching from red meat to plant-based and fish-based diets results in a lower risk of heart disease and stroke.
Population studies have shown that a high dietary intake of omega-3 fatty acids is linked to a reduced risk of dementia, as well as a reduction in high blood pressure and heart disease.
However, clinical studies with omega-3 dietary supplements for the treatment or prevention of dementia such as Alzheimer’s have shown little or no benefit.
In my opinion, like many Mediterranean-style diets, a diet high in fruits and vegetables, legumes, nuts, and oily fish has many health benefits, including lower risk of dementia and vascular disease.
If you enjoy eating beef, I recommend that you only do it occasionally. Until there are clear benefits showing that grass-fed beef has health benefits compared to grain-fed beef, I think eating beef sparingly is far more important than being grass-fed.