Taking some fish oil may help you achieve a six-pack faster, according to a study in the International Journal of Obesity. In the study, participants were given either sunflower oil or DHA-rich fish oil. Research subjects were divided into exercisers and non-exercisers. The exercise group was instructed to exercise at 75 percent of their maximum heart rate for 45 minutes, three times a week. The fish oil and exercise people experienced decreases in body mass greater than any of the other groups combined. The combination of fish oil supplementation and regular aerobic exercise may enhance fat loss.1 Recently, researchers from Spain reported that if you are dieting, fish or fish oils may reduce appetite. In the study, obese subjects were placed on a calorie-restricted diet were divided into four groups:
Diet 1: No seafood
Diet 2: Lean fish (150g of cod/three times a week)
Diet 3: Fatty fish (150g of salmon/three times a week)
Diet 4: Fish oil capsules (six capsules a day – 1,300mg)
The subjects who ate dinners rich in omega-3 fatty acids (diets 3 and 4) felt less hunger and fuller directly after and 2 hours after eating, compared to their counterparts fed with the low omega-3 fatty acid diet. This observation indicates that omega-3 fatty acids reduce hunger signals. The researchers speculated that omega-3 fatty acids affect the transport of appetite-regulating molecules and changes in receptor affinity in the brain.2 The researchers followed these participants over time and at the end of the study, even though calories were closely monitored and subjects ate the same total calories, the control group not taking fish/fish oils lost 2.2 pounds less than the fish/fish oil groups.3
That being said, more people will likely consume more fish to enhance weight loss. Before you start eating fish with every meal, there is some controversy going on as to what type of fish (farm raised versus wild) and which fish to eat (salmon, cod, tilapia, catfish, etc.) as well. Additionally, the health benefits of fish have been questioned due to high levels of contaminates found in fish.
References
1. Hill AM, Buckley JD, Murphy KJ, Howe PR. Combining fish-oil supplements with regular aerobic exercise improves body composition and cardiovascular disease risk factors. Am J Clin Nutr, 2007 May;85(5):1267-74.
2. Parra D, Ramel A, Bandarra N, Kiely M, Martínez JA, Thorsdottir I. A diet rich in long chain omega-3 fatty acids modulates satiety in overweight and obese volunteers during weight loss. Appetite, 2008.
3. Gunnarsdottir I, Tomasson H, Kiely M, Martinéz JA, Bandarra NM, Morais MG, Thorsdottir I. Inclusion of fish or fish oil in weight-loss diets for young adults: effects on blood lipids. Int J Obes, (Lond), 2008 Jul;32(7):1105-12.