What is the Glycemic Index and Why Should You Care?

You may have heard a lot about GI or glycemic index recently.  Many well known food products use ‘low GI’ as a marketing message, promising ‘long lasting energy’.   Other products simply boast the small GI symbol on their packaging.  There is a GI diet, and many recipe books and magazines feature recipes that are low GI.  But what exactly is GI and is a diet based on low GI foods beneficial for our health?

What is GI?

GI or glycemic index is a rating system from 0 to 100, based on the effect that a food has on blood sugar levels when it is eaten. Only foods containing carbohydrates can have a GI rating, as carbohydrates are broken during digestion to their simplest form, sugars.   High GI foods with ratings of 70 or more are those which are digested and absorbed quickly, causing a rapid increase in blood sugar, usually followed by a substantial drop in levels.  Low GI foods, with a rating less than 55 on the other hand, are absorbed and digested more slowly and therefore cause a more gradual rise in blood sugar levels that is maintained over a longer time frame.

Why is GI important?

The GI of the food you eat is important for everyone.  Quick rises in blood glucose levels, such as those produced by high GI foods, can cause us to feel hungry again soon after eating.  This is due to the rapid drop of the blood sugar after the initial peak.  Low GI foods however, can keep you full for longer, as your blood sugar is maintained at a constant level over an extended period of time.

Maintaining blood sugar levels at a constant level is particularly important for people with Diabetes.  Type 2 Diabetics do not respond to insulin, a hormone in the body that regulates blood sugar levels by allowing the uptake of sugar into the cells for energy.  If people with diabetes experience large increases in blood sugar levels, over time, this can do extensive damage to the body.

GI is also important when doing sport.  Athletes need to eat the correct foods for training and competing to ensure their blood sugar levels stay constant.  Exercise increases insulin production, so if a person does a lot of exercise their blood sugar levels can drop very low.  An athlete may need to eat high GI foods before competing or during a race to boost depleted levels of blood sugar quickly.

What are the benefits of a low GI diet?

A low GI diet has proven benefits for health. A diet based on low GI foods can be beneficial for weight control, due to delayed hunger and appetite control produced by stabilized blood sugar levels.  This means that you eat less overall, contributing to weight loss or control, and are less likely to crave high sugar and calorie foods.

Insulin resistance is also reduced with a low GI diet.  When the body is constantly producing insulin to facilitate the uptake of glucose into the cells of the body and reduce the blood glucose levels, eventually the body can become resistant to this insulin.  This means that blood sugar levels stay high, which can do damage to blood vessels and organs in the body.  This is how type 2 Diabetes usually develops.

The Harvard School of Public Health has performed studies that suggest that the risk of lifestyle diseases such as Type 2 Diabetes and heart disease are related to the overall GI of a person’s diet, and that a lower GI diet reduces risk of these conditions.  The World Health Organisation (WHO), recommends that people living in industrialised countries should follow a low GI diet to reduce risk of these common diseases.

What are some low GI food options?

So we know a low GI diet can have health benefits, but what foods should we actually be eating?  Choosing healthy low GI options can be more difficult that it seems.  Whilst fresh foods are easy to identify as low or high GI, composite foods made up of multiple ingredients can be more difficult.  Unfortunately, foods with a high fat content usually have a low GI.  This is because fat slows gastric emptying and therefore increases digestion time.  Ice cream and chocolate are both relatively low GI foods, but are obviously not healthy choices and are likely to contribute to weight gain. See also how to read a nutrition label 

Combinations of foods in a meal can also affect blood sugar levels.  If a high GI and low GI food are eaten together for example, the effect will be a moderate rise in blood sugar levels.  An example of this is eating a potato with baked beans, the potato is high GI, but the beans are low, so the effect on blood sugars is moderated.

For optimum results it is best to eat low GI foods the majority of the time, however, if the occasion arises where this is not possible, try to at least combine high GI choices with lower GI options to reduce the effect on your blood sugars. See also: What are the healthiest foods to lose weight

Easy low GI food swaps

Cereals

Swap puffed rice cereals (GI 82), cornflakes  (GI 80)and puffed wheat  (GI 80) for porridge (GI 58), natural muesli  (GI 40) or All-Bran (GI 50)

Bread

Swap white bread (GI 71), baguettes (GI 98) and bagels (GI 72) for wholewheat(GI 49), soya and linseed  (GI 36)or sourdough (GI 54).

Swap taco shells (GI 68) for wheat tortilla (GI 30)

Fruit

Swap dates (GI 103) for prunes (GI 30)

Swap watermelon (GI 80) for apples (GI 34)

Vegetables

Swap potatoes (GI 60) for sweet potatoes (GI 48)

Swap pumpkin (GI 75) for carrots (GI 41)

Most vegetables are quite low in carbohydrates and have a low GI

Snack foods

Swap pretzels (GI 83) for nuts (GI 13-25)

Swap water crackers (GI 78) and rice cakes  (GI 87)for oatmeal crackers (GI 55)

Swap maple flavoured syrup (GI 68) for  jam (GI 51) or Nutella (GI 33)

Swap scones (GI 92) and donuts  (GI 76) for a nut and seed muesli bar (GI 49).

Pasta and rice

Swap short grain rice (GI 83) for long grain (GI 50) or brown rice (GI 50)

Swap rice noodles for wheat pasta (GI 54) or instant noodles (GI 47)

Dairy

All dairy products are low GI with the exception of ice cream which is classified as medium (GI 62)

Legumes

All legumes are low GI.

Source

Type 2 Diabetes: How to Lose Weight

Weight loss is a common recommendation for treatment for type 2 diabetes. Many people are overweight when they’re first diagnosed, and that extra fat actually increases their insulin resistance (when their bodies can’t properly use the hormone insulin).

By losing weight, people with type 2 diabetes can become less insulin resistant, and they’re able to use insulin better.

If you’ve recently been diagnosed with type 2 diabetes and you're overweight, you should get started as soon as possible on a weight loss plan. It is important to work with a registered dietitian to help you figure out a plan that will work for you—a healthy meal plan, physical activity, and realistic goals will help you reach a healthy weight.

There are many advantages to losing weight (and not just diabetes-related ones):

• Boost your energy level
• Lower your cholesterol levels (especially important for people with type 2 diabetes)
• Protect your heart (also important for people with diabetes, since heart-related complications are very common)
• Make it easier to control your blood glucose level

As you may already know, losing weight can be a challenge, but don’t let that stop you. Do whatever you need to in order to stay motivated.

It is the amount of calories we eat that contributes to weight gain. Make small changes. Learn portion sizes and reduce the amount of snacks in your day to reduce the total amount of calories you consume each day. Find cookbooks with healthier recipes using low-fat options.

Work with a registered dietitian who specializes in diabetes to help you set reasonable goals.

Physical activity can help with weight loss, and in the article on exercising when you have type 2 diabetes, you can learn about how to start an exercise plan.

A Final Weight Loss Note

For some people, losing weight doesn’t help them have better control of their blood glucose levels, and that’s all right. They may need to use medications or insulin to keep their blood glucose level in the normal range, but they should also still eat healthy foods and increase physical activity.

Everyone should strive for a healthy weight. Losing weight can help lower your body’s insulin resistance, but if it doesn’t help you achieve better blood glucose control, that doesn’t mean you’ve failed—or that you should give up. Losing weight and then maintaining a healthy weight are healthy choices for life—whether you have type 2 diabetes or not.

Source
http://www.endocrineweb.com/conditions/type-2-diabetes/type-2-diabetes-how-lose-weight
SOURCES:

• American Diabetes Association.  Standards of Medical Care in Diabetes—2009. Diabetes Care.2009;32:S13-61.
• Becker G. Type 2 Diabetes: An Essential Guide for the newly Diagnosed. 2nd ed. New York, NY: Marlowe & Company; 2007.
• McCulloch D. Patient information: Diabetes type 2: Overview. UpToDate Web site. January 30, 2009. Available at: http://www.uptodate.com/patients/content/topic.do?topicKey=~n0K0MIfI1iZs.&selectedTitle=5~150&source=search_result. Accessed April 20, 2009.
• McCulloch D. Patient information: Diabetes mellitus type 2: Overview. UpToDate Web site. December 4, 2008. Available at: http://www.uptodate.com/patients/content/topic.do?topicKey=~X0jjLnBn4._ko&selectedTitle=4~150&source=search_result. Accessed April 20, 2009.

Diabetes and Weight Loss: Finding the Right Path

If you've got diabetes, losing weight can get you off insulin and other medications. Create a safe diabetes weight loss plan with the help of experts.

There's no question about it: If you're overweight and have type 2 diabetes, dropping pounds lowers your blood sugar, improves your health, and helps you feel better.

But before you start a diabetes weight loss plan, it's important to work closely with your doctor or diabetes educator - because while you're dieting, your blood sugar, insulin, and medications need special attention.

Make no mistake -- you're on the right path. "No matter how heavy you are, you will significantly lower your blood sugar if you lose some weight," says Cathy Nonas, MS, RD, a spokeswoman for the American Dietetic Association and a professor at Mount Sinai School of Medicine in New York City.

A National Institutes of Health study found that a combination of diet and exercise cuts the risk of developing diabetes by 58%. The study involved people who were overweight (average body mass index of 34) and who had high -- but not yet diabetic -- blood sugar levels.

"We know it's true -- that if someone with diabetes loses 5% to 10% of their weight, they will significantly reduce their blood sugar," Nonas tells WebMD.

"We see it all the time: people can get off their insulin and their medication," she says. "It's wonderful. It shows you how interwoven obesity and diabetes are."

Even losing 10 or 15 pounds has health benefits, says the American Diabetes Association. It can:

• Lower blood sugar
• Reduce blood pressure
• Improve cholesterol levels
• Lighten the stress on hips, knees, ankles, and feet

Plus, you'll probably have more energy, get around easier, and breathe easier.

On a Diabetes Weight Loss Plan, Watch for Changes in Blood Sugar

Cutting back on just one meal can affect the delicate balance of blood sugar, insulin, and medication in your body. So it's important to work with an expert when you diet.

Check with your doctor before starting a diabetes weight loss plan, then consult with a diabetes educator or nutritionist, advises Larry C. Deeb, MD, a diabetes specialist in Tallahassee, Fla. and president-elect of the American Diabetes Association.

"Don't try to lose weight on your own," says Deeb. "With a doctor and a good nutritionist, it's very safe to do. This is very important if you're taking insulin or medications."

Go for the Right Balance in a Diabetes Weight Loss Plan

Christine Gerbstadt, MD, a spokeswoman for the American Dietetic Association, warns: "You don't want to run the risk of high or low blood sugar while you're dieting," she tells WebMD. "You want tight glucose control while you lose weight."

Gerbstadt suggests cutting 500 calories a day, "which is safe for someone with diabetes," she says. "Cut calories across the board -- from protein, carbohydrates, and fat -- that's the best way." She recommends that people with diabetes maintain a healthy ratio of carbs, fat, and protein. The ideal:

• 50% to 55% carbs
• 30% fat
• 10% to 15% protein

Watch the Carbs in a Diabetes Weight Loss Plan

For people with diabetes, a refresher course on carbs may also be in order, Gerbstadt says.

That's because carbs have the biggest effect on blood sugar, since they are broken down into sugar early in digestion. Eating complex carbs (whole-grain bread and vegetables, for example) is good because they are absorbed more slowly into the bloodstream, cutting the risk of blood sugar spikes, Gerbstadt explains.

"Worst case scenario is sliced white bread," she says. "Whole-wheat bread is an improvement. Adding a little peanut butter is even better."

Simply cutting lots of carbs -- a common dieting strategy -- can be dangerous, Gerbstadt says. When your body doesn't have carbs to burn for fuel, your metabolism changes into what's known as ketosis -- and fat is burned instead. You'll feel less hungry, and eat less than you usually do -- but long-term ketosis can cause health problems.

"Ketosis decreases oxygen delivery to the tissues, which puts stress on eyes, kidneys, heart, liver," Gerbstadt says. "That's why the low-carb, high-protein Atkins diet is not really safe for people with diabetes. Diabetics need to try to stick with a more balanced diet so your body can handle nutrients without going into ketosis."

Special Challenges When Following a Diabetes Weight Loss Plan

"For anyone, losing weight is challenging enough," Luigi Meneghini, MD, tells WebMD. Meneghini is director of the Kosnow Diabetes Treatment Center at the University of Miami School of Medicine. "For people who inject insulin, it's even more difficult because they have to eat when they have low blood sugar. When you have to reduce calorie intake, prevent over-medication, and eat to correct your low blood sugar, it's very challenging."

Indeed, both low and high blood sugar levels are the two big concerns for people with diabetes.

Low Blood Sugar (hypoglycemia) occurs when the amount of insulin in the body is higher than your body needs. In its earliest stages, low blood sugar causes confusion, dizziness, and shakiness. In its later stages, it can be very dangerous -- possibly causing fainting, even coma.

Low blood sugar is common when people lose weight because cutting calories and weight loss itself affect blood sugar levels. If you don't reduce your insulin dosage or pills to match new blood sugar levels, you'll be risking high blood sugar.

High Blood Sugar (hyperglycemia) can develop when your body's insulin level is too low to control blood sugar. This happens when people on insulin or sugar-lowering medications don't take the correct dose or follow their diet.

The Effects of Exercise on Diabetes

One of the benefits of exercise is that it helps keep your blood sugar in balance, so you won't have to cut as many calories.

"Walk an extra 20 minutes a day, and you can eat a little bit more," Gerbstadt explains, and instead of cutting 500 calories, "you can cut back just 200 or 300 calories, and still get excellent results in weight loss. You'll also control your blood sugar. And the weight will be more likely to stay off if you lose it slowly, safely."

Keep in mind: Each type of exercise affects blood sugar differently.

Aerobic exercise -- running or a treadmill workout -- can lower your blood sugar immediately.

Weight lifting or prolonged strenuous exercise may affect your blood sugar level many hours later. This can be a problem, especially when you're driving a car. It is one of the many reasons that you should check your blood sugar before driving. It's also a good idea to carry snacks such as fruit, crackers, juice, and soda in the car.

"With physical activity, you burn blood sugar as well as sugar stored in muscle and in the liver," explains Meneghini. "People using insulin or medications to simulate release of insulin should closely monitor blood sugar levels when they begin exercising more. Over time, as you exercise regularly, you can reduce doses of medications and insulin."

Getting Started on Your Diabetes Weight Loss Plan

Losing weight is never easy. That's where a diabetes educator or a nutritionist can help, advises Deeb. A diabetes educator or nutritionist can develop a program that fits you and your lifestyle -- a program with realistic goals, he says.

"You will need a meal plan, one that you can follow every day. You'll need to know how to alter your insulin and medication based on what you're eating and whether you're exercising more," Deeb tells WebMD. "That's the safest way to lose weight."

A consultation with a diabetes educator or dietitian/nutritionist can cost from $60-$70. Typically, insurance covers the first two visits, but may not cover additional visits, says Meneghini.

Reasonably priced diabetes support groups and classes are available, frequently through hospitals. Ask your doctor or physician assistant for recommendations.

There are also diabetes web sites with in-depth exercise and weight loss information, including:

• American Diabetes Association at www.diabetes.org
• National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK) diabetes.niddk.nih.gov

"Information is power, and the better informed you are, the better decisions you can make," says Meneghini.

Source
http://www.webmd.com/diabetes/features/diabetes-weight-loss-finding-the-right-path

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Reviewed on October 28, 2011

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