Re: dizziness while exercising
Good! Increasing exercise and loss of body fat may help you stop the progression to diabetes.
But have you mentioned the dizziness during exercise to your doctor?
You may want to add some strength training to build and maintain muscle mass -- increased muscle mass will increase your metabolism and help burn fat even at rest. Pushups, pullups, dips, and other bodyweight exercises can be done at home without requiring a lot of equipment.
As far as what to eat goes, when eating carbohydrate foods, choose lower glycemic higher fiber foods, like vegetables (other than potatoes), whole fruit, and beans, instead of sugar, sweet drinks, and non-whole grain.