How To Combat Gylcation With A Low Glycemic Diet
In our previous blog posts we've discussed AGEs and the glycation process and the damaging effects it can have on the state of your skin and wellness. We've also discussed measures to combat this, such as a diet low in sugar or with our targeted anti-glycation beauty-boosting supplement S-Block.
This post will further provide ways to combat glycation with a low GI diet, including what it is, how to follow it, and its benefits and drawbacks.
The low glycemic (low GI) diet is based on the concept of the glycemic index (GI). Studies have shown that the low GI diet may result in weight loss, reduce blood sugar levels, and lower the risk of heart disease and type 2 diabetes.
Much of the average diet contains carbohydrates (breads, cereals, fruits, vegetables, and dairy products), when consumed your digestive system breaks it down into simple sugars that enter the bloodstream. Not all carbs are the same, as different types have unique effects on blood sugar.
The glycemic index (GI) is a measurement system that ranks foods according to their effect on your blood sugar levels. It was created in the early 1980s by Dr. David Jenkins, a Canadian professor. The rates at which different foods raise blood sugar levels are ranked in comparison with the absorption of 50 grams of pure glucose. Pure glucose is used as a reference food and has a GI value of 100.
The three GI ratings are:
- Low: 55 or fewer
- Medium: 56–69
- High: 70 or more
Foods with a low GI value are the preferred choice. They’re slowly digested and absorbed, causing a slower and smaller rise in blood sugar levels. On the other hand, foods with a high GI value should be limited. They’re quickly digested and absorbed, resulting in a rapid rise and fall of blood sugar levels.
You can use this database to find the GI value (and glycemic load, described below) of common foods.
It’s important to note that foods are only assigned a GI value if they contain carbs. Hence, foods without carbs won’t be found on GI lists. Examples of these foods include:
A number of factors can influence the GI value of a food or meal, including:
- The type of sugar it contains. There’s a misconception that all sugars have a high GI. The GI of sugar ranges from as low as 23 for fructose to up to 105 for maltose. Therefore, the GI of a food partly depends on the type of sugar it contains.
- The structure of the starch. Starch is a carb comprising two molecules — amylose and amylopectin. Amylose is difficult to digest, whereas amylopectin is easily digested. Foods with a higher amylose content will have a lower GI.
- How refined the carb is. Processing methods such as grinding and rolling disrupt amylose and amylopectin molecules, raising the GI. Generally speaking, the more processed a food is, the higher its GI.
- Nutrient composition. Adding protein or fat to a meal can slow digestion and help reduce the glycemic response to a meal.
- Cooking method. Preparation and cooking techniques can affect the GI too. Generally, the longer a food is cooked, the faster its sugars will be digested and absorbed, raising the GI.
- Ripeness. Unripe fruit contains complex carbs that break down into sugars as the fruit ripens. The riper the fruit, the higher its GI. For example, an unripe banana has a GI of 30, whereas an overripe banana has a GI of 48.
The rate at which foods raise blood sugar levels depends on three factors: the types of carbs they contain, their nutrient composition, and the amount you eat.
However, the GI is a relative measure that doesn’t take into account the amount of food eaten. It’s often criticised for this reason. To solve this, the glycemic load (GL) rating was developed. The GL is a measure of how a carb affects blood sugar levels, taking both the type (GI) and quantity (grams per serving) into account.
Like the GI, the GL has three classifications:
- Low: 10 or fewer
- Medium: 11–19
- High: 20 or more
The GI is still the most important factor to consider when following the low GI diet. However, the Glycemic Index Foundation, an Australian nonprofit raising awareness about the low GI diet, recommends that people also monitor their GL and aim to keep their total daily GL under 100. Otherwise, the easiest way to aim for a GL under 100 is to choose low GI foods when possible and consume them in moderation.
Benefits of A Low GI Diet
Studies have shown that the low GI diet may also have other health benefits:
Low GI diet and diabetes. Diabetes is a complex disease that affects millions of people worldwide. Those who have diabetes are unable to process sugars effectively, which can make it difficult to maintain healthy blood sugar levels. A number of studies suggest that low GI diets reduce blood sugar levels in people with diabetes.
- Improved cholesterol levels. One study showed that low GI diets reduce total cholesterol by 9.6% and LDL (bad) cholesterol by 8.6%. LDL cholesterol is also associated with an increased risk of heart disease and stroke.
- May help you lose weight. Some evidence suggests that low GI diets can promote fat loss. However, more research is needed to determine whether low GI diets are effective for long-term weight loss.
- May reduce the risk of cancer. Some studies suggest that people who consume high GI diets are more likely to develop certain types of cancer, including endometrial, colorectal, and breast cancer, compared with people on low GI diets.
- May reduce the risk of heart disease. Recent research has strongly associated high GI and GL diets with an increased risk of heart disease.
There’s no need to count calories or track your protein, fat, or carbs on the low GI diet.
Instead, the low GI diet involves swapping high GI foods for low GI alternatives.
There are plenty of healthy and nutritious foods to choose from. You should build your diet around the following low GI foods:
- Bread: whole grain, multigrain, rye, sourdough
- Breakfast cereals: steel cut oats, bran flakes
- Fruit: apples, strawberries, apricots, peaches, plums, pears, kiwi, tomatoes, and more
- Vegetables: carrots, broccoli, cauliflower, celery, zucchini, and more
- Starchy vegetables: sweet potatoes with an orange flesh, corn, yams, winter squash
- Legumes: lentils, chickpeas, baked beans, butter beans, kidney beans, and more
- Pasta and noodles: pasta, soba noodles, vermicelli noodles, rice noodles
- Rice: basmati, Doongara, long grain, brown
- Grains: quinoa, barley, pearl couscous, buckwheat, freekeh, semolina
- Dairy and dairy replacements: milk, cheese, yogurt, coconut milk, soy milk, almond milk
The following foods contain few or no carbs and therefore don’t have a GI value. These foods can be included as part of the low GI diet:
- Fish and seafood: including salmon, trout, tuna, sardines, and prawns
- Other animal products: including beef, chicken, pork, lamb, and eggs
- Nuts: such as almonds, cashews, pistachios, walnuts, and macadamia nuts
- Fats and oils: including olive oil, butter, and avocado
- Herbs and spices: such as garlic, basil, dill, salt, and pepper
To search for foods not found on this list, refer to this database.
Foods To Avoid On A Low GI Diet
Nothing is strictly banned on the low GI diet. However, try to replace these high GI foods with low GI alternatives as much as possible:
- Bread: white bread, bagels, naan, Turkish bread, French baguettes, Lebanese bread
- Breakfast cereals: instant oats, Rice Krispies, Cocoa Krispies, Corn Flakes, Froot Loops
- Starchy vegetables: Désirée and Red Pontiac potato varieties, instant mashed potatoes
- Pasta and noodles: corn pasta and instant noodles
- Rice: Jasmine, Arborio (used in risotto), Calrose, medium-grain white
- Dairy replacements: rice milk and oat milk
- Fruit: watermelon
- Savory snacks: rice crackers, Corn Thins, rice cakes, pretzels, corn chips
- Cakes and other sweets: scones, doughnuts, cupcakes, cookies, waffles, cakes
- Other: jelly beans, licorice, Gatorade, Lucozade
Although the low GI diet has several benefits, it also has a number of drawbacks.
First, the GI doesn’t provide a complete nutritional picture. It’s important to also consider the fat, protein, sugar, and fiber contents of a food, regardless of its GI.
For example, the GI of frozen french fries is 75. Some varieties of baked potato, a healthier alternative, have a GI of 93 or more.
In fact, there are many unhealthy low GI foods, such as a Twix bar (GI 44) and ice cream (GI 27–55 for low fat versions).
Another drawback is that the GI measures the effect of a single food on blood sugar levels. However, most foods are consumed as part of a larger mixed meal, making the GI difficult to predict in these circumstances.
Lastly, as mentioned earlier, the GI doesn’t take into account the number of carbs you eat. However, this is an important factor in determining their effect on your blood sugar levels.
For example, watermelon has a high GI of 72–80 and therefore wouldn’t be considered the best option when following a low GI diet. However, watermelon also has a low carb content, containing under 8 grams of carbs per 100 grams. In fact, a typical serving of watermelon has a low GL of 4–5 and a minimal effect on blood sugar levels.
This highlights that using GI in isolation may not always be the best predictor of blood sugar levels. It’s important to also consider the carb content and GL of a food.
While the low glycemic (low GI) diet has a number of potential health benefits, including reducing blood sugar levels, aiding weight loss, and lowering your risk of heart disease and type 2 diabetes, the diet also has multiple drawbacks. At the end of the day, it’s important to consume a healthy, balanced diet based on a variety of whole and unprocessed foods, regardless of their GI.