Researchers measured the MSG consumption of more than 10,000 adults in China over the course of roughly 5.5 years, weighing each participant before and after they were tracked for the study. On average, those with the highest MSG intake were 30% more likely to become overweight by the end of the study than those who consumed the least of the flavoring agent. After excluding those who were overweight at the beginning of the study, that figure rose to 33%.
Lead researcher Ka He, a nutrition expert at UNC, told Reuters Health that the implications of his MSG findings substantial, since “everybody eats it.”
The researchers collected data from the China Health and Nutrition Survey (CHNS), a prospective open-cohort, nationwide health and nutrition survey, consisting of 10,095 apparently healthy Chinese adults aged 18-65 at entry from 1991-2006.
He and co-workers reported that men and women who ate the most MSG (an average of 5g per day) were around 33% more likely to become overweight by the end of the study than those who ate the least amount of the flavoring (average of less than 0.5g per day).
The researchers said this increase was not simply because people were eating more food, some of which happened to have more MSG in, noting that the link between high MSG intake and being overweight held even after accounting for confounding factors including age, physical activity, total energy (calorie) intake, and other major lifestyle factors.
He and colleagues concluded that additional studies are needed “to elucidate mechanisms of action and to establish causal inference.”
Authors noted the following additives always contain MSG, even if it is not expressly written:
• Hydrolyzed vegetable protein
• Hydrolyzed protein
• Hydrolyzed plant protein
• Plant protein extract
• Sodium caseinate
• Calcium caseinate
• Yeast extract
• Textured protein
• Autolyzed yeast
• Hydrolyzed oat flour
From the May 31, 2011, Prepared Foods' Daily News.