Fish collagen hydrolysates or peptides orally administered have been investigated in recent clinical trials in human health. These peptides have been evaluated in various biological and medical fields including skin aging, osteoarticular apparatus, muscle and more recently in energy metabolism in both animals and humans.

However, very few studies investigated the effect of fish collagen peptides on weight, body composition or glycemic response. Recently, it has been shown that the consumption of fish collagen peptides (Naticol®) limits weight gain and increase in fat mass in a mouse model made obese by a hyperlipidic diet. Since these results have never been observed in humans, this pilot study proposes to answer this question.

Inclusion Criteria:

• Men in overweight (BMI between 25kg/m² and 30kg/m²)
• Aged from 18 and 60 years
• Having signed the informed consent form;
• Susceptible to follow the constraints generated by the study;

Exclusion Criteria:

• Subject treated for type 1 or 2 diabetes, or for any other metabolic disorder (severe dyslipidemia: TG> 3 g / L and total cholesterol> 2.5 g / L);
• Subject with untreated and uncorrected high blood pressure;
• Subject with untreated or uncorrected dysthyroidism by drug therapy;
• Subject with a serious general illness that may prevent his or her ability to complete the trial or that could bias the results of the study;
• Subject consuming antibiotic treatment in the month prior to inclusion;
• Subject treated with steroidal anti-inflammatory drugs, anabolic steroids, anticoagulants or corticosteroids;
• Subject knowing allergy to fish or fish collagen;
• Subject taking any dietary supplement or drug that may interact with the results of the study or that could alter the bioavailability of the product under study;
• Subject following or having followed a low-calorie diet (energy intake <1500 kcal / day) in the 3 months preceding inclusion and / or likely to undertake this diet during the test;
• Subject having lost more than 5% of his initial weight during the last 3 months;
• Subject following a special diet: eg. vegetarian, macrobiotic diet, high protein diet;
• Subject with diagnosed eating disorders (anorexia, bulimia);
• Subject with gastrointestinal malabsorption such as celiac disease, Crohn's disease or lactose intolerance;
• Subject having undergone bariatric surgery;
• Subject with excessive alcohol consumption at more than 3 drinks a day ;
• Subject planning to modify his tobacco consumption (eg weaning) or his level of physical activity (significant increase) before the end of the intervention period;
• Subject having an aversion to the grapefruit aroma;
• Subject unable to understand or adhere to the protocol;
• Subject participating in another clinical study or exclusion period from another study;

To avoid action of femal hormone, this pilot study is based on male population