New research confirms some of the basic tenets of the Wheat Belly, a book by Dr. William Davis, which argues that wheat avoidance results in healthy weight loss.
Published in Journal of Nutritional Biochemistry this month, and titled "Gluten-free diet reduces adiposity, inflammation and insulin resistance associated with the induction of PPAR-alpha and PPAR-gamma expression," researchers compared the effects of a gluten-based diet to a gluten-free diet in mice.
Gluten exclusion (protein complex present in many cereals) has been proposed as an option for the prevention of diseases other than coeliac disease. However, the effects of gluten-free diets on obesity and its mechanisms of action have not been studied. Thus, our objective was to assess whether gluten exclusion can prevent adipose tissue expansion and its consequences.
Mice were fed either a high-fat diet containing 4.5% gluten (Control) or no gluten (GF). The researchers then assessed the following 16 parameters in both groups:
- Body weight
- Adiposity gains
- Leukocyte rolling and adhesion
- Macrophage infiltration
- Cytokine production in adipose tissue
- Blood lipid profiles
- Glycaemia (blood sugar)
- Insulin resistance
- Expression of PPAR-α and γ
- Lipoprotein lipase (LPL)
- Hormone sensitive lipase (HSL)
- Carnitine palmitoyl acyltransferase-1 (CPT-1)
- Insulin receptor
- Adipokines in epidymdimal fat
Remarkably, they found that, relative to the gluten-fed mice, the gluten-free animals showed a reduction in body weight gain and adiposity, without changes in food intake or lipid excretion.
We interpret this to mean that the weight gain associated with wheat consumption has little to do with caloric content per se; rather, the gluten proteins (and likely wheat lectins) disrupt endocrine and exocrine processes within the body, as well as directly modulating nuclear gene expression, e.g. PPAR-α and γ, in such a way as to alter mammalian metabolism in the direction of weight gain.
Sometimes we forget that food is not simply a source of energy, or the material building blocks for the body, but a source of information as well. The way in which food directly interacts with the genes, gene expression, or gene product structure and function, is the object of study of the burgeoning new field of nutrigenomics. Wheat, like anything we attempt to use as food, contains both energy/matter and information that the body will use to maintain its genetic integrity or that may interfere with it.