English to Spanish Medical Nutrition

It's a document on sugars and body weight control:

This review covers evidence from carefully controlled laboratory studies, clinical trials, studies in populations at high risk of developing obesity, and epidemiologic studies on the role of sugars, particularly sucrose, in the development of obesity. Although many environmental factors promote a positive energy balance, it is clear that the consumption of a low-carbohydrate, high-fat diet increases the likelihood of weight gain. The evidence related to carbohydrate, particularly sugars, and the type of food (solid or liquid) is less clear because the number of long-term ***ad libitum dietary intervention trials*** is very small. Data on sucrose intake in relation to metabolism and weight gain do not associate high consumption of sucrose with the prevalence of obesity.

¿estudios de intervención nutricional?
Gracias! =)