Diet plays an indisputable role in controlling diabetes and is one of the pillars to stop the progression of this disease. Everyone is clear that it is convenient to reduce sugar intake as much as possible, but it is not the only thing that must be taken into account. A key aspect is to follow a diet with a low glycemic index.
The glycemic index (GI) measures the ability of a food to increase blood sugar (glucose) levels after ingestion. Only foods that contain carbohydrates have a GI. To calculate it, pure glucose is taken as a reference, whose GI is set at 100, and it is compared with each food.
It is considered that they have a low GI those foods that are at 55 or below, medium those that score between 56 and 69 and high from 70. In this way, simple carbohydrates (such as sucrose or common sugar) they have a high GI, as do honey, white bread and even some others that are less suspicious, such as cooked carrots (raw has a low GI).
Glycemic index: key against diabetes
A study carried out by researchers from the Obesity and Nutrition Network Biomedical Research Center (Ciberobn), led by Jordi Salas-Salvadó, and the Universities of Toronto and Zagreb, has just confirmed that diets with a low glycemic index are a tool essential to control and prevent type 1 and 2 diabetes. This systematic review of clinical trials, published in the British Medical Journal, finds, as Salas-Salvadó explained to CuídatePlus, that in patients with diabetes “a low glycemic index of the diet it is related to lower levels of glycosylated hemoglobin, which tells us the levels of glycemia (blood glucose) of a person in the last three months. Likewise, a reduced GI “is associated with different changes in cardiovascular risk factors: lower risk of having high LDL (bad) cholesterol, lower levels of triglycerides, lower level of adiposity and better levels of systolic blood pressure.”
In the words of the researcher, this is “the best evidence we have at the moment to be able to tell a patient with diabetes that, regardless of whether they take insulin or oral antidiabetics, diet is something important.” Moreover, he believes that from now on “all diabetic patients should be recommended to follow low glycemic index diets.”
How to Follow a Low Glycemic Index Diet
To follow a diet with a low glycemic index that makes it possible to control or stop diabetes, it is necessary to understand that the GI cannot be considered in isolation, but rather interacts with other aspects. Remember that raw carrots have a low GI. However, with cooking it rises because the sugars separate and become more accessible. Something similar happens with pasta: al dente has a lower glycemic index than when it is overcooked.
As far as fruit is concerned, it is worth knowing that the GI is higher when it is green and rises the riper it is. However, at this point a new parameter must be introduced, the glycemic load (GL), which takes into account the amount of carbohydrates in a given food. A high GI in a food rich in carbohydrates is not the same as that same GI in a product with a much lower quantity. Hence, in many cases, as is the case with most fruits, it is necessary to resort to the GL measurement, which is calculated by dividing the food’s glycemic index by 100 and multiplying by the amount of carbohydrates in grams it has. the evaluated ration.
The cooked carrot is another good example that the glycemic load provides relevant data. Although its GI is very high, it does not have too many carbohydrates and contains a lot of fiber, so its GL is low.
Another example of how the GI varies when a food is processed: eating a piece of fruit is not the same as consuming it in the form of juice. When an orange is squeezed, the GI of the resulting juice is higher because some of the fiber is removed, which serves to delay the passage of sugars into the digestive system.
Therefore, the GI does not only depend on the type of food, but also on other characteristics, such as the way it is prepared, the variety (for example, it changes depending on whether the rice is short or long grain), whether it is whole or not (whole grains have a lower GI) and the foods with which it is combined. Boiled white rice has a higher GI than paella, since it also contains vegetables, oil and other products.
Taking all of the above into account, these are, for reference, the GIs of some of the most common foods:
Glucose: 100
Cooked Carrot: 92
Honey: 87
Instant mashed potatoes: 80
White rice: 72
Cooked potato: 70
White bread: 69
Brown rice: 66
Banana: 62
sweet corn: 59
Peas: 51
Refined flour paste: 50
Grapes: 45
Whole wheat pasta: 42
Orange: 40
Apple: 39
Tomato: 38
Chickpeas: 36
Whole milk: 34
Lentils: 29
Sausages: 28
Soy: 15
Peanuts: 13
Lettuce: 15
Some foods with a low glycemic index, such as sausages, are not recommended in the usual diet of any person, including patients with diabetes. In fact, dietitians-nutritionists and nurses who are in charge of their nutritional education usually warn them that oils, fats and meats have no GI, but they can also affect blood sugar levels.
Most recommended foods against diabetes
Salas-Salvadó advises patients with diabetes, as well as those who want to prevent this disease, to opt for food options with a low GI whenever possible. For example, to satisfy hunger in the middle of the afternoon, he proposes eating a handful of hazelnuts instead of a few bars of bread, since “they have a very high glycemic index, which makes sugar rise quickly, so that after two or three hours there is a decrease in sugar that generates more appetite and, in addition, favors the deposit of fat, which in turn promotes weight gain. On the other hand, hazelnuts, although they have the same calories, “do not produce that increase in glucose after the meal, so the appetite does not increase after a couple of hours and the risk of weight gain is reduced.”
These are the foods that should predominate -in different proportions, depending on their GI and other considerations- in a diet aimed at preventing or controlling diabetes:
Fruits and vegetables.
Whole grains.
Legumes.
Nuts.
Extra virgin olive oil.
Fish.
White meats.
As far as legumes are concerned, the Ciberobn researcher points out that “among the foods that contain carbohydrates, they are among those with a lower glycemic index.”
