DASHing to the “best diet” a critique

The DASH diet is currently hailed as the best diet by U.S News. So what is it? In a nutshell it advocates low-salt, low saturated fat, low cholesterol, more fiber, more fruits, more vegetables, and limited sweets while increasing physical activity. Its designed to hopefully decrease your blood pressure and weight. Oh and check it out, its got the U.S Department of Health and Human Services stamp of approval:

So how dramatic are these changes? Saturated fat drops to less than 7% of our daily calories and cholesterol to 150 mg in their studies…that’s less than a large egg! Carbohydrates, as usual, compose the majority of the diet and salt drops to 2.3 grams.

But how different is this diet really? Let’s compare its recommended servings to something a lot of us grew up familiar with:

VS

Grains are both 6-11 servings between the old food pyramid and the 1600-2600 calorie DASH diets
Vegetables are increased by one serving in the DASH if you are in the 2600 calorie group
Fruits take an increase with a minimum of 4 and up to 6 servings in the 2600 calories group for DASH
Milk products are the same except they must be fat free or low fat in the DASH diet
Meat takes a huge upswing with 3 more servings in the DASH diet
Nuts gets their own segment but in both cases, they recommend very little nut consumption
Fats get separated from Sweets in the DASH diet with 2 servings

So in summary the DASH diet still holds grains as their foundation, with a little more vegetables, a lot more fruit, fat free or low fat milk, and more lean meat. The basic foundation is still carbohydrates, and one can argue you’d consume more carbohydrates on the DASH diet with the increase in fruits and vegetables.

Now its being touted as being able to control cholesterol, triglycerides, weight, and insulin resistance along with blood pressure! But is it really the DASH diet by itself or something else? One study examined this through separating participants into 3 different groups: DASH diet alone, DASH with weight management strategies (psychological motivation, weight reduction and exercise training), or a usual diet control group through a 4 month session:

Effects of the dietary approaches to stop hypertension diet alone and in combination with exercise and caloric restriction on insulin sensitivity and lipids.
From: http://ukpmc.ac.uk/articles/PMC2874827

The two different DASH diets did show decreases in blood pressure compared to the control group but that’s about it. When the DASH alone is compared with the control diet there is no difference in glucose metabolism, insulin sensitivity, cholesterol, triglycerides, LDL levels and HDL levels. The control group did gain an average of 1.2 kg compared to the DASH diet alone…but when you look into the data you’ll find that the Dash diet alone group ate 1962 calories vs the control’s 2095. Is it really that surprising that the control group gained 1.2 kg with 133 more calories ingested everyday spread across 4 months?

It’s only when you add weight management strategies with the DASH diet that you see changes across all measures. Couldn’t it just be the exercise and weigh reduction making the difference? Yes the DASH did lower BP, but couldn’t that just be the lowered salt consumption? Why the need to target fat and cholesterol consumption (especially saturated fat) so much? Btw…even the salt restriction is debatable more on that in future posts…

So is the DASH diet bull? Not necessarily. It may work for some and fail for others in lowering blood pressure and perhaps even the other previously discussed measures. The important point is to not view it as a universal diet panacea that will work for everybody just because a publication hails it as the “best” diet.

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