Genetic Weight Loss Control: Creating the Perfect Program for Your Patients

Nutrigenomics can be used in two different ways. The first way is to provide a better understanding of nutrition as it applies to the general population. The second way is to provide an understanding of nutrition at the level of the individual, exploring how nutrients affect people differently, depending on genetic variation.²

Consider what happens, biologically, when we eat a meal. Until quite recently, most scientists thought food had basically one job: it was metabolized to provide energy for the cell. Indeed, that is what happens to most dietary compounds but not all. Some don't get metabolized at all; instead, the moment they're ingested, they peel off and become ligands, molecules that bind to proteins involved in "turning on" certain genes to one degree or another.

A diet that's particularly out of balance, nutritional-genomics scientists say, will cause gene expressions that nudge us toward chronic illness unless a precisely-tailored "intelligent diet" is employed to restore the equilibrium.³Here's a good example of how this works: if you're of northern European ancestry, you can probably digest milk, and if you're Southeast Asian, you probably can't. In most mammals, the gene for lactose tolerance switches off once an animal is weaned. Humans shared that fate until a mutation in the DNA of an isolated population of northern Europeans around 10,000 years ago introduced an adaptive tolerance for nutrient-rich milk. The likelihood that you tolerate milk depends on the degree to which you have northern European blood.³

A role for genetic predisposition to obesity has been shown to exist, and it is estimated that 40-70% of the variation in obesity-related phenotypes is heritable.⁴

The idea of the DNA diet is rooted in the scientifically proven reality that dieting simply doesn't work for many people. According to studies, 95% of people will gain back the weight they lose within a few years, and 41% of those who attempt dieting will eventually gain back more weight than they lost.⁵ Genetic polymorphisms affect the metabolism of dietary factors, which in turn affects the expression of genes involved in a number of important metabolic processes. Genetic polymorphisms affecting nutrient metabolism may explain some of the inconsistencies among epidemiological studies relating diet to chronic diseases.⁶ 

A study conducted at Stanford University looked at the long-term effects of weight loss using a few different diets assigned at random. Results showed that some participants lost weight on one type of diet, such as low-fat, while others did not. The study then tested participants' DNA for 3 specific gene variations and found that those using the best diet for their DNA lost as m����������������es more weight than those not using their best DNA diet.⁵ This can be explained from a nutrigenomics perspective: nutrients are dietary signals that are detected by the cellular sensor systems that influence gene and

protein expression, and subsequently metabolite production. So, patterns of gene expression, protein expression and metabolite production in response to particular nutrients or nutritional regimes can be viewed as "dietary signatures."⁷

Here are examples of three DNA-based diets-- low-fat, low-carb, and balanced -- and how to determine which may be best for your genetic makeup:

May be best for your DNA if you have:

• Heart disease in your family
• Low energy levels
• High LDL cholesterol

A low-fat diet can provide weight loss and protect you from diseases you're predisposed to. Avoid fatty foods, refined sugars and carbohydrates: they can make you feel lethargic. For best energy, eat low-fat carbs, including whole grains like quinoa, or legumes, like black beans. Choose monounsaturated fats like olive oil and avocado to improve your HDL cholesterol.

May be best for your DNA if you have:

• Weight around your midsection
• High blood pressure
• High triglycerides

If your waist is greater than 35 inches, you're at risk for heart disease, gall bladder disease and diabetes. You may be insulin resistant, which means you have difficulty processing sugar. By losing 10% of your body weight, you can also lower your blood pressure. Choose lean healthy proteins and limit the amount of carbs, especially refined white foods like starchy potatoes and bread.

May be best for your DNA if you have:

• Family history of diabetes or heart disease
• Mediterranean ethnicity
• Frequent indigestion or constipation

In a recent study,⁸ researchers was found that the addition of nutrigenetically tailored diets resulted in better long-term BMI reduction and improvements in blood fasting glucose. Interestingly, the performance of the two groups over the first few months was very similar in terms of weight lost. However, after one year, the non-tested control groups showed a slight average weight gain while the nutrigenetic tested group continued to lose weight, although at a lower rate than during the first 90 days. This suggests that compliance to the weight management programs was better in the nutrigenetics tested group, achieving long-term lifestyle changes and resulting in sustained weight loss and improved blood fasting glucose levels. 

The number of diet-gene interactions that are sufficiently well-understood to lead to specific and helpful advice is very small, and the number of relevant genetic variants for which it is practical or feasible to screen is even smaller; a condition like obesity can involve hundreds of genes interacting in complex ways.⁹ Genetic testing is still in its nascent stage so a combination of exercise, diet control and nutrigenomics could work to bring the body weight in the healthy range and get rid of associated health problems.

1. Studies on nutrients, gene expression could lead to tailored diets for disease prevention. Kansas state university, Science daily; Mar 7, 2010
2. Nutrigenomics and beyond: Informing the future -- workshop summary. Ann L. Yaktine and Robert Pool, 2007, p. 8
3. Eat right for your genotype. Bruce Grierson, The Guardian; May 15, 2003
4. Does weight loss prognosis depend on genetic make-up? M. J. Moreno-Aliaga, J. Santos, A. Marti and J. A. Martínez, Obesity reviews Vol. 6, p. 155-168
5. Exploring the perfect diet for your genes, Aug 2, 2010. WWW.DOCTORZ.COM
6. Nutra genetics. El Sohemy A. Forum of nutrition, 2007(60), p- 25-30
7. Nutragenomics goals and strategies. Michael Muller and Sander Kersten, J of Am Diet Assoc 101, 1306, 2001.
8. Improved weight management using genetic information to personalize a calorie controlled diet. Ioannis Arkadianos, Ana M Valdes, Efstathios Marinos, Anna Florou, Rosalynn D Gilland Keith A Grimaldi. Nutrition Journal 2007, 6:29
9. Your genomic diet: your genomic profile could be the key to knowing what to eat and staying healthy. Technology review (Cambridge, MA), Aug '05.

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