Avoid a Sedentary Lifestyle, Avoid Processed and Convenience Foods

"The health benefits of a low-carb diet may not only depend on the types of protein and fat, but also the quality of carbohydrate remaining in the diet."
"Our findings show clearly that the quality rather than the quantity of macronutrients in our diet has an important impact on our health."
"The debate on the health consequences of low-fat or low-carbohydrate diets is largely moot unless the food sources of fats or carbohydrates are clearly defined."
Dr.Zhilei Shan, post-doctoral researcher, Department of Nutrition, Harvard University

"In this study, overall low-carbohydrate-diet and low-fat-diet scores were not associated with total mortality. Unhealthy low-carbohydrate-diet and low-fat-diet scores were associated with higher total mortality, whereas healthy low-carbohydrate-diet and low-fat-diet scores were associated with lower total mortality."
"These findings suggest that the associations of low-carbohydrate and low-fat diets with mortality may depend on the quality and food sources of macronutrients."
Study researchers

"It's more about selecting whole natural or minimally-processed foods, regardless of the amount of carbs or fat."
"This would translate into a diet that may include a variety of whole foods in various combinations including fruit, vegetables, legumes, nuts and fish as well as whole fat dairy and unprocessed red meat and poultry."
Andrew Mente, associate professor, Health Research Methods, Evidence, and Impact. McMaster University, Hamilton

Exchanging carbohydrates for plant-based fats and proteins might promote healthy ageing  Getty Images

A newly-published study out of Harvard University where researchers followed 37,233 adults for two decades published in JAMA Internal Medicine, posits that people who follow low-carb or low-fat diets may not live longer than others, unless they also take care to avoid junk food and sweets in their daily diet. Study participants were 50 years old on average, when the study began. During the period of the study 4,866 people died, representing about 13 percent of participants.

The researchers reported that overall, mortality rates for people who followed low-carb or low-fat diets and those who did not, had similar outcomes in longevity. Still, risk of premature death for people on these diets who consumed healthier foods such as plant proteins --  unsaturated fats and good quality carbohydrates such as vegetables, fruits, legumes and whole grains -- did appear to be lower.

Mortality, on the other hand, was higher for people who included a lot of saturated fats and animal protein in their diets. Those who received most calories from unhealthy foods were 16 percent likelier to die during the study period, among low-carb dieters than those people who followed the healthiest diets. People were 12 percent more likely to die who took most of their calories from unhealthy foods with low-fat diets.

National dietary surveys conducted between 1999 to 2014 provided data leading to the findings when participants were asked to recall everything they had eaten in the previous 24 hours. 849 people died from heart disease and 1,068 of cancer, during the study period -- with several types of cancer and many cardiovascular diseases associated with unhealthy diets.

The analysis sees a limitation in that researchers were able to score participants' diet quality based solely on their recollection of a single day's intake of food. Without viewing the possibility that some of those same people might have altered their eating habits over time. What occurs in the body when people consume various types of carbs or fats that might impact longevity is not really known, points out Kevin C.Maki, researcher at Indiana University.

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