Sugar and Fat – and Diet Research
While we know that sugar is a key element of the obesity equation, it’s difficult to design a perfect diet because biochemical pathways and their communication with the brain do not necessarily translate to the combination of motivation and weight loss effect you would expect.
One diet study published last year showed the effects of two different diets on people with type 2 diabetes.1 Both diets were low in calories and saturated fats. The difference was that one diet was rich in unsaturated fats and proteins and low in carbs (58% fat / 28% protein / 14% carbs). The other diet was high in carbs, with less fats and proteins (30% fat / 17% protein / 53% carbs). People in both groups reduced their weight and glycated hemoglobin, a marker of diabetes, by the same amount. However, the low carb diet – with the higher unsaturated fats - produced better glucose stability and a better lipid profile.
Associating a high unsaturated fat diet (which would include avocadoes, nuts and vegetable oils) with a better lipids profile is not intuitive.
As a matter of fact, another 2017 study showed that across the globe and regardless of income, people in the highest quintile of carbohydrate consumption had higher mortality than the lowest quintile.2 The opposite was shown for fat (all types) and protein: The highest quintile of fat and protein consumption had the lowest mortality - also not intuitive.
Among other findings that would strike our common sense as odd is that if you replace 5% of carbs with the same amount of calories from saturated fat, you can decrease the risk of stroke by 20% (and in the study, it didn’t change overall mortality).
While trying to make sense of which healthy diet to follow, we not only have special interest groups constantly bombard us with consistent advertising messages that their products are good for us, but we see inconsistent messages from the scientific community (as theories and counter-theories fight it out). At least now scientific journals do realize the importance of disclosing the sources of funding for the research studies they publish. (My last blog on sugar and obesity discusses this.)
Nonetheless, the U.S. is slowly trending towards a healthier diet. A recent study showed that in the decades between 1999 and 2002 and between 2009 and 2012, the median consumption of fruits increased over 500%; the consumption of whole grains and nuts also increased; and drinking sugar-sweetened soft drinks decreased.3 However it’s disturbing to find that the analysis also found an increase in the amount of processed meat consumed, while the amount of sodium had a small increase, both affecting mortality negatively.
It is obvious how the information from these studies could be of interest and affect you personally, but as life insurers, reinsurers and therefore as students of mortality, we have a vested interest in understanding what drives obesity and diabetes, two important drivers of past and, clearly, future mortality.
- J. Tay et al., Nutrition & Diabetes, volume 7:304 (2017).
- M. Dehghan et al., Lancet, 390 (10107), 2050-2062, 2017 Aug 29.
- R. Micha, et al., JAMA, 2017 Mar 7.