Eating-it is lifestyle
Glycemic index concept was developed in 1981 by Dr. David Jenkins, a professor of nutrition at the university of Toronto, Canada to figure out which food will be better choice for patients with diabetes. So, high glycemic index food will rapidly increase blood sugar level, low glycemic index food will do it slowly and not for such degree. It was established that low GI food ( carbohydrates)-55, medium-56-69, high-70 and more.
On the low GI diet you can eat lean meat, some poultry, a lot of fish, fruits and vegetables, cheese, a lot of legumes –they have the lowest GI.
This is carbs controlled diet, not low carb- low fat-high protein diet, this diet based on choosing right type of carbohydrates-slowly digested and absorbed. Majority of diets call for reduced caloric intake, so you will lose some weight while you are on this diet, then when you back on your regular diet you will gain the same weight or even more. Why? Because you mostly lose water and muscle, not fat tissue, if you doing this many times it will be more difficult to lose fat. Low glycemic food has ability to feed you faster and keep you feeling full longer, it will increase your metabolic rate.
The higher metabolic rate, the easier to lose weight, because your cells will be more sensitive to insulin and blood sugar level will be normalized, so –less insulin and more lypolysis-more fat will be burned.
The 7 guidelines of low glycemic diet:
#1. Eat 7 or more serving of fruits and vegetables a day.
Fruits and vegetables play a central role in LGI diet, they have a lot of fiber, also vitamins, minerals, antioxidants, phytochemicals.
It is better to have : 2 serving of fruits and 5 servings of vegetables, 1 serving- cup of raw or ½ cup of cooked veggies, 1 medium size fruit. Most veggies have low GI, but some high, for example-potatoes, so it can be replaced with low GI food, in this case-corn, sweet potatoes, yam. You can eat greens how much you want, just remember that olives and avocado have high GI, they have a lot of fat, but it is good one. Berries have the lowest GI in all fruits: strawberry, blueberry, blackberry.
#2. Eat low GI breads and cereals. The type of bread you eat effects GI the most.
Mixed grains bread, whole wheat bread, traditional rolled oats, barley, pasta, bulgur wheat, buckwheat, brown rice-examples of low GI food. Most people need 4 servings of grains a day, 1 serving-2 slices of bread or ½ cup of rice, pasta.
#3. Eat more legumes including beans, chickpeas, lentils-they are Nature’s the lowest GI food, high in fiber, protein, manganese, vitamins, have them at least 2 serving a week.
#4. Eat nuts more regularly, most nuts high in fat but they have low content of carbohydrates, have vitamins-Vit E and antioxidants, have at least 1 handfull a week.
#5. Eat more fish.
Fish does not have GI because it is not a carbohydrate, but it has a lot of good fat- Omega 3 fatty acid which has a lot of good properties that we already discussed. Especially good to eat : wild salmon, herring, mackerel, sardines, 3-4 serving of fish a week will very good for you.
#6. Eat lean meat, poultry and eggs, these foods do not have GI – it is mostly proteins, iron, fat soluble vitamins, eat 2-3 servings of these foods a week.
#7. Eat whole fat dairy-milk, cheese, yogurt, custard- it is the main source of calcium besides green leafy vegetables rich in calcium too.
Key factors that influence the Glycemic Index
- Cooking methods: when food exposed to water the swelling of starches occurs (gelatination), that leads to increase of enzymatic activity and increase of glycemic index. Corn flakes, pop corn, rice cakes- examples of food with increased GI due to cooking.
- Amount of fiber- the more fiber content, the low GI of food, the longer it takes to digest and assimilate it.
- Type of starch -There are two types of starch: amylase and amylopectin, the more amylase food contain, the lower GI, examples of such food: legumes, brown and basmati rice. Amylopectine is a larger molecule, but due to chemical structure it can be broken easier, so it will be digested faster and such food will have higher GI.
- The amount and type of sugar will determine food’s GI.
- Food with high concentration of fructose ( apples, oranges) have low GI because body digest fructose in a way that blood sugar level-glucose level will be slow increased. There is concept of Glycemic Load – it depends on the amount and types of carbohydrates . GL=GI value multiply by amount of carbs per serving and divided by100
GI Dietary Philosophy is:
- Low GI carbohydrates 40-50% of daily calories, monosaturated fats -30-35%, proteins-15-20%.
- The average energy regimen for young to middle age men-2400 calories a day.
- 90-120gr. of protein, 80-95gr. of fat, 250-300gr. of carbohydrates.
- For young to middle age women-2000- calories, 75-100gr of protein, 70-80gr. of fat and 210-250 gr. of carbohydrates a day.
- For older women and low energy intake men: 1500 calories, 55-75gr. of protein, 50-60gr. of fat and 150-200gr. of carbohydrates.
A lot of math, it looks too much, but if you really want to, you will figure it out, GOOD LUCK !
Glycemic Cooking Made Easy by Dr. Jennie Brand-Miller, Kaye Foster-Powell, and Joanna McMillan-Price, Rodale Inc. 2007