Glycemic index, Glycemic load, and Diabetes 2

Diabetes Mellitus Type 2 (T2DM) is a non communicable disease that has seen a demographic shift in past few decades. Glycemic index is system of assigning a value (numerical 1-100) to dietary products containing carbohydrates based on by 'how much it increases the blood sugar levels upon consumption'. In a meta analysis by Zafar et al., 2019, it was shown how low glycemic index diet was effective in reducing HBA1c levels along with fasting glucose (FPG) levels. This indicated that lesser the glycemic index better the control over increased glucose levels hence the diet suggested by GP's which is predominantly a low carb diet. I also think that unprocessed foods containing fibers, proteins etc. have low glycemic index as compared to processed and refined food products. This also corroborates that while our demography shifts rapidly towards consumption of processed food products, a part of this demography that either has diabetes or is at risk of diabetes, has now more risk associated due to their dietary and lifestyle patters.

Glycemic load estimates the amount of carbohydrates (in grams) per serving of food consumed. Glycemic load is a better indicator to ascertain how much food/ serving should be consumed to achieve a targeted amount of carbohydrates. Example: Glycemic load calculates how many carbohydrate units are there in say 100 grams of cooked white rice. Hypothetically, if there are 10 grams of carbohydrates in 100 grams of cooked white rice, then a person with T2DM can calculate how much of that food product they must be consuming to get a targeted amount of carbohydrates. It gives a person better sense of control over their diet. In recent technology awake, there are several applications that enable consumers to track their calories, serving sizes, proteins, water intakes etc. to achieve certain health target. While we know how carbohydrate rich diet causes spikes in blood sugar levels, if an understanding of how much is made available, one can control their blood glucose levels.

To conclude, I think that glycemic load is a better indicator to control T2DM for groups that can understand its technicality but glycemic index is a better tool for masses to understand who, generally, might not make sense of these terms.

As per a study I came across, the mechanism where high levels of glycemic load-based diets can increase the risk of type 2 diabetes is as follows;

• High glycemic load leads to counterregulatory hormones that increase levels of late postprandial free fatty acids directly increasing insulin resistance.
• This increased insulin resistance results in a higher insulin demand, causing beta-cell exhaustion (leading to hyperglycemia, most risk variants for type 2 diabetes act via impairment of insulin secretion (Cerf et al., 2013)) and glucose intolerance leading to diabetes.
• Another pathway directly links high glycemic load to high insulin demand due to factors attributed to insulin resistance via genes, inactivity, and obesity, leading to beta-cell exhaustion and ultimately diabetes.

It is also mentioned that both glycemic load and index contribution of an individual’s overall diet has been associated with a higher risk of type 2 diabetes. It is also suggested that replacing carbohydrates from their high-glycemic-index forms with low glycemic index forms will reduce the risk of type 2 diabetes as this would improve glycemic control and reduce hypoglycemic episodes. (Willett et al., 2002). As per this, we can further reflect on the association between glycemic index, glycemic load, and the risk of type 2 diabeties.

Studies reported substituting low-glycemic-index carbs for high-glycemic-index carbs reduces the incidence of type 2 diabetes as it

improves glycemic control and reduces hypoglycemia episodes in diabetic individuals. The low-risk dietary pattern has also been linked to a decreased risk of coronary heart disease as well as a lower risk of diverticular disease and constipation making it an appropriate component of overall healthy diet guidelines.

Read here

//pubmed.ncbi.nlm.nih.gov/12081851/

While we talk about diets which are low in carbohydrates and in their glycemic index, I would also like to mention how our demography is majorly a rice consuming one and other dietary products which are a rich source of carbohydrates. I wonder how our population as such during this changing epidemiological trend will combat these chronic NCDs while looking at dietary patterns at its center?

Recently, there has been an uproar of a new product which acts as a sensory glucose monitoring patch which can be applied topically. While it is a smart way to predict and monitor glucose spikes and falls and thus monitor the course of treatment, its sustainability in terms of cost and affordability is a question. Can there be novel yet simpler ways to reach masses? Example: Alongside nutrition index given on any consumable, glycemic index can also be mentioned.