Much has been written on the internet about carbohydrates and type 2 diabetes. Time once again to bust myths in the health and nutrition world!
If you have searched the internet, you will have read some video or article by various self-proclaimed health and nutrition experts about carbohydrate consumption and whether it can contribute to or lead to type 2 diabetes.
But if you want the truth, you're in the right place, because here we present scientific research and evidence without mincing words.
Type 2 diabetes is a severe non-communicable chronic disease described by reduced insulin action or secretion or reduced response of the body's cells to insulin, followed by the inability of the endocrine pancreas to compensate for this impaired response.
So far, they had been held three meta-analyses in order to study the correlation between carbohydrates and the risk of type 2 diabetes, but the results were inconsistent.
A publication from the PURE study in 21 countries around the world had found higher rice consumption to be associated with a higher risk of type 2 diabetes, with the strongest association in South Asia, while there was no statistical association in other regions of the world.
A recent systematic review and meta-analysis, sought to clarify the association between carbohydrate intake and type 2 diabetes risk by examining the possible variation in effects by geographical location.
CARBOHYDRATES AND RISK OF TYPE 2 DIABETES
So let's start by looking at the findings of this meta-analysis.
The limitation of dose-response analyses to studies exclusively from Western countries suggests that the risk of type 2 diabetes has no appreciable changes with an increase in carbohydrate intake from 37 to 60% of total calories, and if present, this increase confers modest protective characteristics.
On the other hand, limiting analyses in Asian studies found that the risk of type 2 diabetes does not change markedly with increasing carbohydrate intake until about 70% of total calories, followed by a steep and linear increase in risk.
Although we could put an epilogue here, there are details that need to be clarified.
What could explain such a large increase in risk when carbohydrate intake exceeds 70% of total calories?
The bad carbohydrates that cause diabetes. Probably not, as 70% is a huge percentage which as we can see from the studies is something not found in the West. In short, if carbohydrates and only carbohydrates were the problem, we wouldn't have such high rates of type 2 diabetes in the West.
As we saw in "Eggs and health", there are large differences in the health effects of food between countries in the West and those in the East. But why is this the case?
Populations living in poorer areas have a higher exposure to heavy metals and chemicals that cause endocrine disruption in general, which very often end up in food. Intake of such substances has been associated with type 2 diabetes and the metabolic syndrome in general.
Based on the theory of developmental roots of health and disease (Developmental Origins of Health and Disease), malnutrition during critical periods of development can damage organ development, ultimately resulting in an increased risk of metabolic diseases such as type 2 diabetes later in life.
It is obvious that when we are talking about populations whose diet is 70% carbohydrates and mostly rice, then the odds probably tend to support the third hypothesis more, less the second, as it is not supported, at least at the moment, by high quality research, and not at all the first.
It is therefore logical and expected that the combination of the studies as a whole gives us the following:
In any case, it seems that not only are carbohydrates not the cause of type 2 diabetes as many blogs and fanfares will have you believe, but the percentage of carbohydrates recommended by dietary guidelines worldwide is not only safe, but rather protective in most cases.
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