Fish oil influences appetite, and generally it suppresses appetite-but not always. Here is a brief explanation of how and when fish oil influences appetite.
How Fish Oil Can Suppress Appetite
Do you ever eat so much you just can't eat any more?
A full stomach, for most of us, causes of feelings of satiety that shut down appetite. Taking fish oil capsules just before a meal can help induce a feeling of fullness that shuts down hunger.
The best quality fish oil capsules contain mostly fat. Fat slows down digestion in the stomach. The stomach has to emulsify the digested fat so that it blends in with the watery products of digesting other major food groups, namely starch and protein. And the presence of fat causes the stomach to take longer to digest protein before releasing the mix into the small intestine.
Actually, taking any kind of plant oil or fish oil supplement 30 to 45 minutes before meal time will reduce appetite by helping you fill up faster. That is the idea behind the Korean pine nut oil supplements so often used in weight control. While there is nothing at all wrong with using Korean pine nut oil to help control appetite, fish oil is less expensive and offers additional benefits in the form of ready-to-use DHA and EPA essential fatty acids that are not found in in pine nut or flaxseed oil.
How Fish Oil Might Not Have Any Effect on Appetite
Not every brand of fish oil, however, will reduce appetite. If you buy brand that uses enteric-coated capsules that break open in the small intestine, not in the stomach, then there is no appetite-killing effect from the product. New Vitality fish oil is enteric-coated, as are Nature's Way, Optimum Nutrition, and Kirkland Signature Fish Oil, the latter brand offered by CostCo. If a product is enteric-coated to prevent fish breath and fishy burps, then it won't reduce appetite.
However, if a product contains at least 300 mg of essential fatty acids in each capsule, as Nordic Naturals, Omega-Brite, and Xtend-Life do, then it wasn't going to cause fish breath or fishy burps and did not need to be enteric coated. (The New Vitality product delivers a very high content of omega-3 essential fatty acids, but is enteric-coated nonetheless.)
And One Situation In Which Fish Oil Might Increase Appetite
The one time taking fish oil might increase appetite is when it is used as a treatment for ulcerative colitis, ischemic bowel disease, or Crohn's disease(read more about fish oil for digestive health). For these conditions, relief of inflammation reduces abdominal pain and makes eating easier. The absence of pain allows eating enough without eating too much.
Frequently Asked Questions
Q. Will taking fish oil help me lose weight?
A. I always answer that question with an unequivocal maybe. Taking fish oil supplements reduces inflammation, so that if you are exercising to lose weight, you are more likely to lose fat weight than muscle weight. And as I mentioned in the article on Fish Oil for Athletes, sometimes even sedentary people lose 1-2 pounds (500 g to a kilo) of weight in a month just by taking fish oil, probably because the fish oil reduces inflammation that causes swelling. But it won't make a huge difference, just a pound or so a month.(more about fish oil and weight lose)
Q. Fishy burps kill my appetite. Is there a way to get the benefits of fish oil without the burps?
A. There was a time when almost all fish oil products caused fish breath, fishy burps, and loose stools. Modern processing that concentrates fish oil and minimizes "marine liquids" in the capsule prevents this problem. The products that offer especially high concentrations of essential fatty acids along with especially low concentrations of "burpable" fish products include Nordic Naturals, New Vitality, Omega-Brite, and Xtend-Life.