Low glycemic index (GI) diet is a diet plan that affects your blood sugar level. The term “high glycemic index diet” refers to this diet plan that uses the index as the primary or sole guide to planning a healthy diet. Unlike some other plans, a low glycemic index diet does not necessarily indicate portion sizes or the optimal number of calories, carbohydrates or fat for weight loss or weight maintenance.
The purpose of the diet is to include in your menu foods that contain carbohydrates that are less likely to cause large increases in blood sugar levels. Diet can prevent chronic conditions, such as obesity, diabetes and cardiovascular disease, also to help weight loss.
Why follow a GI diet
Choose to follow such a diet if:
- you want to lose weight and maintain a healthy weight;
- you need to plan and eat healthier foods;
- you need to maintain blood glucose levels as part of a plan for treating diabetes.
Many scientific studies suggest that a GI diet can help achieve these goals. Talk to your doctor before you start a weight loss diet, especially if you have health problems like diabetes.
The glycemic index
The principle of GI was originally developed to support the choice of food for people with diabetes. The GI database is maintained by the Glycemic Index University of Sydney, Australia and contains the results of studies conducted at other research centers around the world.
Carbohydrates are nutrients that have three main forms: sugars, starch and fiber. When you take foods and drinks containing carbohydrates, your body breaks down sugars and starches into a type of sugar called glucose.
Two hormones, which are produced by the pancreas, help regulate blood glucose. The hormone insulin drives blood glucose into cells. The hormone glucagon helps to release glucose stored in the liver when blood sugar is low. This process helps our body maintain good energy levels and provides a natural balance of blood sugar.
Carbohydrate foods affect how quickly your body absorbs them and how fast glucose enters your bloodstream.
Understand GI values
There are different methods of examining GI in your diet, based on how well a food product raises your blood glucose levels. The GI values are usually divided into three categories:
- Low GI: 1 to 55
- Average GI: 56 to 69
- High GI: 70+
Comparing these values will help you better target healthier foods.
Limitations on GI values
One notable drawback of the GI values is that they do not reflect the likely amount you would eat from a particular food. For example, watermelon has a GI value of 80, which would put it in the category of foods to avoid, although there are relatively low-digestible carbohydrates in a typical serving. This means you need to eat a lot of watermelon to increase significantly your blood glucose level.
To address this problem, researchers have developed the idea of glycemic load (GT) – a numerical value that indicates the change in blood sugar levels when you eat a typical meal.
For example, a serving of 4.2 oz (120 grams) watermelon has a GT value of 5, which would qualify it as a healthy food choice. For comparison, serving 2.8 oz (or 2/3 cups) of raw carrots has a GT 2 value.
The GI table of values from the University of Sydney is usually grouped as follows:
- Low GI: 1 to 10
- Average GI: 11 to 19
- High GI: 20 or more
How Low Glycemic Foods Help Weight Loss
The ability of this low glycemic index diet plan to aid weight loss has been widely discussed by scientists, but there is still no consensus on whether eating low-GI foods is better for losing weight than traditional diets.
Those who eat only low-GI foods believe that this will increase their metabolic rate and increase their satiety, but determining the true effect of low-GI eating on the weight loss process is quite complicated.
As the body converts different types of carbohydrates into sugars at different speeds, low and high GIs have been found to show how quickly a particular diet affects blood sugar levels.
Low GI foods cause a slow increase in blood glucose and slow, controlled release of insulin, which is good for weight loss. On the other hand, foods with a high percentage of GI cause a fast rise in glucose levels, but in this way insulin increases rapidly, which is not good when weight loss and maintaining good health is your goal .
Low GI Diet and Diabetes
Diabetes is a complex disease that affects millions of people around the world. Those who suffer from it are unable to process sugars effectively, which can make it difficult to maintain healthy blood sugar levels. Good blood sugar control helps prevent and delay the onset of complications, including heart disease, stroke and nerve and kidney damage.
Studies show that low glycemic diets are effective in reducing blood sugar levels in people with diabetes. One study of nearly 3,000 people with diabetes looked at the effect of low- and high-GI diets on participants’ glycated hemoglobin (HbA1c) levels over a three-month period.
The study reveals that HbA1c levels are 6-11% lower in those who consume diets with the lowest GI (GI 58-79) compared with those who consume diets with the highest GI (GI 86-112). In other words, low GI diets were associated with lower blood sugar levels in the long run.
Moreover, a number of studies report that diets with a higher glycemic index can increase the risk of type 2 diabetes by 8-40%. A low GI diet can also improve pregnancy outcomes in women with gestational diabetes mellitus (GDM), a form of diabetes that occurs during pregnancy.
Other studies show that such a diet also reduces the risk of macrosomia by 73%. This is a condition in which newborns have a birth weight of over 8 pounds and are associated with many short and long term complications for the mother and baby.
A one-week sample menu with a low glycemic index for weight loss
The following sample menu will show you what a week of low GI diet might look like.
- Breakfast: Oatmeal with sliced fresh fruit
- For lunch: Chicken sandwiches with whole grain bread and salad
- Dinner: Veal meatballs with vegetable salad and brown rice
- For breakfast: Whole-grain roasted avocado, tomato and smoked salmon
- Lunch: Vegetable soup with a slice of whole grain bread
- For dinner: Grilled fish with broccoli and green beans
- For breakfast: Omelette with mushrooms, spinach, tomato and cheese
- Lunch: Fish, ricotta and quinoa with salad
- For dinner: Homemade pizza with whole wheat and other ingredients of choice
- For breakfast: Mashed berries, banana, yogurt and cinnamon
- For lunch: Chicken salad with wholegrain spaghetti and vegetables of your choice
- For dinner: Homemade burgers with vegetables and whole grain bread
- For breakfast: Quinoa porridge with apples and cinnamon
- For lunch: Toasted whole grain sandwich with tuna salad
- For dinner: Chicken with curry and basmati rice, chickpeas
- For breakfast: Avocado fruit and vegetable smoothies, whole grain baked slices
- For lunch: Boiled eggs, tomatoes and olives wrapped in lettuce
- For dinner: Grilled lamb chops with stewed vegetables and roasted pumpkin
- Breakfast: Buckwheat pancakes with berries
- For lunch: Brown rice and tuna and tomato salad
- For dinner: Beef, lightly fried with vegetables, served with long grain rice
Disadvantages of a low glycemic index diet
Although a low GI diet has several advantages, it also has several disadvantages. First, the glycemic index is unable to provide a complete nutritional picture. It is also important to take into account the fat, protein, sugar and fiber content of a food, regardless of its genetic turnover.
For example, the glycemic index of French fries is 75, while their healthier substitute – baked potatoes, has a higher GI – 85.
In fact, there are many unhealthy, low-GI foods such as ice cream (GI 36-62), chocolate (GI 49) and egg cream (GI 29-43).
Another disadvantage is that the glycemic index does not take into account the number of carbohydrates consumed. This is an important factor in determining their effect on blood sugar levels and effects on weight loss.
A low glycemic index diet involves replacing foods with high GI for low GI alternatives. It has a number of potential health benefits, including supporting weight loss, reducing blood sugar levels and reducing the risk of heart disease and type 2 diabetes.
At the end of the day, the most important thing is to eat healthy, balanced foods based on a variety of whole foods and unprocessed foods, regardless of their GI.