Science on nutrition is proving that there are now healthy and unhealthy carbohydrates. They are using the glycemic index to be able to determine the healthier carbohydrates.
Glycemic Index for Good and Bad Carbs: The Glycemic index measures how fast and how far blood sugar (glucose) rises after you eat a certain carbohydrate source of food. For example, white bread is considered to be a high glycemic index food. This is because it is quickly digested and absorbed into the blood stream. This consequently increases the blood sugar level very high and very fast. On the other hand whole wheat bread is digested much more slowly. This causes a lower and more gentle change in blood sugar level so it is said to have a low glycemic index
Key Details of glycemic index for good and bad carbs
| Topic | Key Points |
| What GI Measures | How fast a carbohydrate raises blood sugar |
| High vs Low GI | High GI = quick spikes; Low GI = slow, steady rise |
| Health Impact | High GI links to diabetes & weight gain; low GI helps manage Type 2 diabetes |
| GI Determinants | Processing, fiber, ripeness, starch structure, fat & acid content |
| Why Whole Foods Matter | Less processed carbs = lower GI & more nutrients |
| Limitations of GI | Varies by food type, prep method, and eating conditions |
Carbohydrate foods with high glycemic index have been linked to increase in both diabetes, unhealthy weight and heart disease while low glycemic index has been shown to control type two diabetes. You will find, even though the food pyramid recommends a mainly plant based nutritional diet, it insists on whole foods. This is because a major determinant of a food’s glycemic index is how processed the carbohydrate is.
How does Glycemic Index for good and bad Carbs help?
The Harvard T.H. Chan School of Public Health defines low-glycemic foods as having a rating of 55 or below and high-glycemic foods as having a value between 70 and 100. Foods in the medium level have a glycaemic index between 56 and 69.
The relationship between carbs and blood sugar or carbohydrate metabolism must be understood in order to comprehend GI. The digestible carbohydrates in food are converted to sugar. Blood sugar levels increase after eating. The hormone insulin is produced by the pancreas. It facilitates the cells’ absorption of blood sugar for storage and energy. Blood glucose levels start to drop as a result of this absorption. The pancreas subsequently generates glucagon, a hormone that accelerates breakdown of glycogen to glucose (glycogenolysis), stimulates glucose synthesis (gluconeogenesis), inhibits glycogen production (glycogenesis), and hence mobilizes export of glucose into the circulation.
Also Read:- What Really Causes Food Cravings and How to Control Them
Also Read:- How the Body Breaks Down Carbs for Energy Into glucose
Low GI = slow sugar release = better for energy, weight control and blood sugar stability.
High GI = fast sugar release = may lead to cravings, overeating and blood sugar spikes.
Some determinants of GI (Glycemic Index) are listed below;
i) Processing: The more finely ground grain is rapidly digested due to increased surface area hence a higher GI. Processing tends to remove the fibre rich outer bran. It also removes the vitamins and mineral rich inner germ, basically stripping the food all its nutrients except carbs.
ii) Fiber-content: The bran for example shields the food from immediate rapid action by enzymes. This slows the enzymes effectiveness in releasing the sugar molecules into the blood stream.
iii) Ripeness: The more ripe a fruit or vegetable the more the sugar it has hence a higher G.I.
iv) Structure of the starch: Occurring in many structural forms, the more a starch isomer is branched the less easily is broken down. For example a potato is more easily broken down because its starch is only a long chain. This makes it a high G.I. food.
v) Fats and acid content: The more fat and acid a food contains the slower its carbohydrates are turned into sugar.
Determining G.I. may end up being a little complicated. A combination of the above factors may have counter-intuitive results. But the rule is simple; always prefer whole grain products and them more natural forms of carbohydrates. Use them more often than highly processed grains, just as recommended in any good weight loss diet.
Weight loss diets are one of the Top 4 Reasons you fail in losing weight permanently. However there are three other factors that you need to effectively tackle to avoid failure in losing weight.
Limitations of the Glycemic Index for good and bad Carbs
GI can be affected by a number of factors, including food variety, growth conditions, minor adjustments to meal preparation, and even the level of mastication. Additionally, GI tables are created using 50 g of a food’s available carbohydrates. It is frequently challenging to reach this level of carbohydrate in ad lib eating circumstances. Here is the Glycemic index for 60+ foods
Some examples for Glycemic Index food
Low GI foods:
- Lentils, chickpeas, kidney beans
- Oats (steel-cut), quinoa, barley
- Sweet potatoes
- Most vegetables
- Apples, berries, oranges
High GI foods:
- White bread, bagels
- White rice, instant rice
- Potatoes (especially mashed or baked)
- Sugary cereals
- Watermelon (despite being healthy in other ways)
Here is the Simple Low Glycemic Index Meal Plan for you
Breakfast: Oatmeal with berries and nuts
Lunch: Grilled chicken with quinoa and steamed vegetables
Snack: Apple + handful of almonds
Dinner: Salmon with sweet potato and greens
Dessert: Greek yogurt with cinnamon
What is the Glycemic Index (GI)?
The GI measures how quickly a carbohydrate-containing food raises blood sugar levels after eating.
What is considered high and low GI?
High GI foods: 70–100 (e.g., white bread) — cause rapid spikes.
Low GI foods: 55 or below (e.g., whole wheat bread) — cause slow, steady blood sugar rise.
Why is GI important for health?
High-GI foods are linked to weight gain, diabetes, and heart disease, while low-GI foods help control Type 2 diabetes and support steady energy.
What factors affect a food’s GI?
Processing, fiber content, ripeness, starch structure, fat content, and acidity all influence GI levels.
Why are whole foods recommended?
Whole, less processed foods retain fiber and nutrients, slow digestion, and lower GI compared to refined carbohydrates.
What are the limitations of GI?
GI can vary with food variety, meal preparation, portion size, ripeness, and chewing. GI tables use 50 g of carbs, which may differ from real-life portions.
