Thursday, August 31, 2017

Go Nuts for the Best Diet

What is the best diet for weight loss? What is the best diet for heart health? Many heart patients are obese and are looking for a good diet to lose weight. Certainly all heart patients would like to follow a diet that would help reduce their risk for further heart problems. What is the data on diets?

There are many different commercial diets available, all of which tout their ability to help people lose weight. There are, however, far fewer rigorous scientific trials studying the various diets.  In an ideal world, the best way to evaluate diets is to study one diet compared to another diet, however this is rarely done. Most diet studies compare patients on a diet to patients not on a diet. In a 2015 review in the Annals of Internal Medicine, the data on eleven weight loss programs were systemically reviewed. The eleven programs were: Weight Watchers, Jenny Craig, Nutrisystem, Health Management Resources (HMR), Medifast, OPTIFAST, Atkins, The Biggest Loser club, eDiets, Lose It!, and SlimFast. There were only 39 randomized, controlled trials available in the medical literature for review and even those had significant shortcomings such as limited duration, high rates of dropout, and poor adherence to the diet programs. It was felt that only two programs, Jenny Craig and Weight Watchers, were able to show weight loss at one year, and their results were only modest at best. Another recent review in the Journal of the American Medical Association showed that all diets produced weight loss at six months and one year compared to no diet at all. Weight loss at six months was greater than at one year, with wide variations (from 22 pounds with Atkins diet to 14 pounds for Jenny Craig). At one year, the variations were minor (from 14 pounds with Jenny Craig to 13 pounds for Weight Watchers). Lastly, the US News and World Report came out with their take on the best diets (http://health.usnews.com/best-diet). They did not use the scientific literature, but based their rankings on a panel of “nationally recognized experts in diet, nutrition and food psychology”.  This method is less rigorous and more prone to opinion and bias. Still, they concurred with the medical literature review ranking Weight Watchers number one and Jenny Craig number three for weight loss.

On the other hand, several diets specifically geared towards heart disease have a solid body of data. The Dietary Approaches to Stop Hypertension (DASH) diet is high in fruits, vegetables, whole grains and low fat dairy products, while low in saturated and total fat content. The DASH diet has been shown to significantly reduce blood pressure in hypertensive patients.  Interestingly, US News and World Report ranked the DASH diet as their number one over all diet for 2015; the fifth year in a row it has been number one.

The Mediterranean diet (http://dietamediterranea.com/en/nutrition/) has become the standard for heart healthy eating, showing reduction in heart disease, stroke, cancer and Alzheimer’s disease and lowering the risk for cardiovascular death. It is a plant-based diet with high intake of olive oil, fruit, nuts, whole grains, moderate intake of fish, poultry and wine and low consumption of red meat and sweets. The Mediterranean diet has not been around for very long. It was first described in the 1950’s in Southern Europe and it is actually a result of post-World War II impoverishment and food restrictions. Despite being born from poverty it is rich in benefits.  It has been studied in primary prevention (preventing patients who do not have heart disease from having a heart attack or stroke) and in secondary prevention (preventing patients who have had heart disease from having another event).  It has been studied in over 100,000 patients. In people who do not have disease, those who follow a Mediterranean diet have a 47% lower risk for developing heart disease. In patients who have had a heart attack, those on the diet lowered their risk of dying from heart disease by 50-70%. The Mediterranean diet isn’t just a diet, but a way of life. In addition to the food content, it is emphasized that the food be savored, that meals be shared with friends and family and daily physical activity be a part of the lifestyle.

Nuts, specifically tree nuts such as walnuts, almonds and hazelnuts, are an integral component of the Mediterranean diet and are high in unsaturated fatty acids, fiber, vitamins and minerals. A recent study of nuts showed that nut consumption of 30 grams (about a handful) per day several times per week decreased the chance of dying from heart disease and cancer. It also lowered the risk for diabetes, obesity, hypertension and inflammatory disease.



So the clear winners are the Mediterranean diet for best overall heart health and the DASH diet for hypertension. Both of these diets are well supported by data and recommendations from the American College of Cardiology. Unfortunately, there is no clear winner for the best diet for weight loss as the data is not as strong.  To find out which weight loss diet is right for you, you must first change the concept of a diet, something you go on and then come off. Instead of going on a diet, you should try to achieve a balanced lifestyle with food consumption that is livable and good for the long term. Therefore the likely answer for the best diet for weight loss is similar to, “What is the best exercise” (Answer, the exercise that you like to do and will stick with).  So pick a diet that suits your tastes best and one that fits your lifestyle and budget. Once you have picked your diet and your exercise regimen, stay with it for the long haul. Just remember to reward yourself with a tasty treat. How about a handful of almonds?

No comments:

Post a Comment