Suppose you are overweight and try your best to eat less and to control your calories. This is a hard job as we all know. The more important is it to get the best effect possible. That is, lose as much weight as you can with a minimum of restriction. Fish may be a good way to reach this goal, at least if you are a man. Everything else being equal, an overweight man can lose one additional kilogram (two pounds) within four weeks if he adds fish to his calorie-restricted diet. This has been shown by Icelandic researchers in a controlled diet trial with more than three hundred young people from their own country, from Ireland and Spain. - (Picture by Nanon @ Flickr)
In women, fish has no such effect. A woman can lose weight by eating less, but she will not lose a single kilogram more by eating fish. Oops. But stay with me, female reader! This is not yet the end of it. The rest of the story will tell you that with fish you most likely will get a better effect of your weight loss.
Fish effects beyond body weight
Eating fish helps to tackle one big problem of being overweight: The body does not pay enough attention to a signal that fat cells are sending. This signal is a hormone called leptin, and it tells the muscles to burn more fat and the brain to damp the appetite. Fish and fish oil make muscles more sensitive to leptin. As more leptin is used, its level in the blood begins to fall, as studies in Australia and in Africa have shown.
Besides this leptin effect fish also has a positive influence on blood fats, blood sugar and insulin, thus boosting the healthy effects of weight loss. In most studies, fish oil has a similar effect.
Take home message
Fish or fish oil may help to boost weight loss and its positive influence on health.