To Carb or not to Carb?


Article courtesy of Donna Hargrove, D.O., FACOG – Nutritional Editor

Poor carbohydrates; so misunderstood. Blamed for all the diet evils of the world including obesity and all it’s related health problems. So many people tell me they have cut carbohydrates out of their diet and then report that they are eating more salads and fresh vegetables (????). Not a day goes by that I don’t try to explain carbohydrates to someone. Yes, they are “complex” yet “simple”. Since so much of what we are faced with in the food world everyday is some form of a carbohydrate, it is easy to see why people get confused. Please read on to discover that all carbohydrates are not created equal.

To begin, let me say this. Carbohydrates are very important to sustaining life. Quite simply one cannot live, for an extended period of time, without these energy producing foods. Of the three nutrition building blocks, carbohydrates, fats, and protein; carbohydrates produce energy (glucose) and is the only fuel our brains can use to function. Fats are part of many chemical processes, like hormone synthesis, and proteins build things like DNA & muscle. That having been said, why then, is there so much hype touting the removal of “carbs” from ones diet to curb weight gain or to remove pounds? Indeed, “carbohydrates” is the buzzword in many weight loss circles, and is blamed as a major cause for the epidemic rise of obesity and diabetes. To what extent do carbohydrates contribute to these ballooning health problems, specifically obesity? To “carb” or not to “carb” may be the current media question but the answer, in my opinion, is “know thy carbs”, as well as thyself.

Energy Input High, Energy Output Low

Weight gains result when we take in more calories (energy) than we use. In other words the intake of energy (glucose or sugar) exceeds the use (exercise) equaling a surplus of energy, which is stored for future use (fat). Consequently the question becomes, how do we balance our food intake with our energy needs to maintain a healthy weight? Well, since energy comes from foods with carbohydrates, and as it turns out carbohydrates are not all alike, it seems that we should first understand which foods have the kind of “carbs” that will reduce the likelihood of storing too much energy.

Which Foods Contain Carbs?

In general, it is easier to point out foods that contain carbohydrates by describing those which do not. Those that do not, are food groups such as protein (fish, meat, poultry) and fats (butter, olive oil, etc.), leaving food groups such as grains, (wheat, oats, barley, etc.), fruits, (oranges, lemons, apples, grapes, etc.), vegetables, (carrots, potatoes, tomatoes, peas, beans, etc.), or nuts, which fit into both the “carb” food group and fat food group. As you can see, the “carb” groups are expansive and can (and should) be a substantial portion of most individual‘s diet. So which contain the “good carbs” (Those that will reduce the likelihood of storing too much energy), and which contain the, for the purpose of this article, “bad carbs” (Those that will increase the likelihood of storing too much energy?)

Too Much Sugar, Too Quickly

To sort this out, without endless physiological and metabolic jargon, let‘s attempt to keep it as simple as possible. As carbohydrates are broken down by enzymes during digestion the resulting sugars (glucose), our primary energy source, enter the bloodstream. Our pancreas produces insulin, which moves the sugars out of the bloodstream to be used for either immediate energy or stored for future energy requirements. Some foods containing carbs are broken down and absorbed slowly into the blood stream whereas others are broken down and absorbed more quickly resulting in higher spikes of blood sugar concentration. The consequence of the latter is that, if there is no immediate need for the high concentration of sugar in the blood, insulin will try to reduce the blood sugar by transporting it for storage in muscle and adipose or fat tissue. In addition it requires more insulin to regulate quickly absorbed sugars. High insulin levels prevent already stored sugar (fat) from being released and used for fuel.  Also, persistently high insulin levels are inflammatory to our blood vessels, increasing risks for cardiovascular disease.

Fresh and Fiber – Key to Complex Carbohydrates

Foods containing complex “good carbs” are fresh fruit, vegetables, nuts and whole grains. These foods may be termed complex because they contain cellulose or “fiber”. The bran and germ of wheat or the membranes found in fresh oranges are considered fiber. Fiber may be defined as plant substances resistant to enzymatic breakdown in the GI track. When you eat a carbohydrate food that contains natural fiber such as whole wheat, fresh oranges, fresh tomatoes, or dried beans, the fiber slows down the absorption of the sugar, (glucose) because it takes longer to break down. Additionally it increases bowel function and helps reduce cholesterol and lipid levels in the bloodstream, each of which is a health benefit.

What Does Increasing Fiber Mean?

Increasing fiber intake means eating the whole food, a dietary change, not adding so called fiber supplements in pill or liquid form. Adding or increasing the consumption of carbs and fiber such as legumes, (fresh or dried peas and beans), fresh fruits, and fresh vegetables (green, yellow, or red), is suggested. Replace products made with refined or enriched cereals or flour, (low or no fiber), with products made with 100% whole grain (high in fiber) like wheat, rye, barley, or changing from white rice to brown or wild rice. Not only will this help with weight maintenance or loss, via slower absorption of glucose and better insulin control, but, in addition, foods containing more fiber cause one to feel full more quickly. Nuts such as almonds, walnuts, peanuts, and pistachios make up a part of the carbohydrate family and are an important source of good fats and fiber. Nuts may be high in calories, which should be taken into account for your daily total caloric intake, so moderation is the word.

The bottom line is that if there is more sugar in our bloodstream than is necessary for immediate energy the surplus is stored as fat. To correct the equation one must either, increase the amount of energy expended, say by exercise, and/or slow down the absorption of the sugars, thereby lowering blood sugar concentration, by changing ones diet.

Good Carbs (complex) vs. Bad Carbs (simple)

A solution to help balance our energy to food ratio would be increasing the intake of “complex carbohydrates”, (good carbs) which slow down the absorption of glucose, and decreasing or eliminating “simple carbohydrates”, (bad carbs) that allow quicker absorption. Since all carbs are not created equal, in metabolic terms, and that carbs are essential to proper bodily functions, for instance brain function and the absorption of vitamins and minerals which is not reproduced simply by swallowing a vitamin pill, then we need to sort out the complex “good carb” foods from the simple, so called, “bad carb” foods.

How Can We Be Sure We‘re Selecting the Right Foods?

Fresh vegetables, fruit, etc., are pretty easy to spot, but what about packaged foods that meet our new requirements? Labeling may be confusing. Some packaged products, cans, boxes, bottles, etc., may lead us to believe we‘re selecting foods with good carbs. Terms like multigrain, whole wheat, “whole grain”, etc., may sound like you‘re getting the good carbs, fiber intact, however the label must say 100% whole wheat, etc. to be, in fact, unrefined with fiber still intact. Refining of flour removes the fiber, and increases the speed of absorption of sugars during the metabolic breakdown. “All natural” shows up on many product labels, however, “All Natural” does not necessarily mean “good carb” or “fiber”. Many people tend to perceive granola bars as a healthy choice full of natural foods. However, many granola bars are full of simple sugars, which are quite “natural” but consequently a poor choice.  White bread, white rice and most white flour pastas are made with refined grains and should be avoided as well as processed breakfast quickies like instant oatmeal. Steel cut oats on the other hand is a good choice due to high fiber content. Avoid pastries, muffins (especially the “super-sized” ones), and bagels (unless you find 100% whole grain bagels) as they are normally high in sugar and refined flours.

All Fruits & Vegetables Are Not Good Carbs

Fruit juices, even 100% juice, seem like a healthy choice. However, fruit juices should be limited during weight loss since the fiber is not retained even in 100% fruit juice. You are better off eating the fresh fruit. The fiber parts of the fruit allow for slow absorption of glucose, resulting in lower insulin levels.  Some fruits cause higher glucose levels, like bananas & pears, so watch how much you eat.

(Note: The Glycemic Load (GL) can be an important tool when trying to choose foods with good carbs.  The GL is the application of the Glycemic Index (GI) to a standard serving of food.  For example: GL = GI X gm of carbohydrate (CHO)/serving.  All food labels list the grams of CHO per serving of a product.  For fresh foods, CHO quantities can be found on many websites.  A 5 oz serving of white rice has a GI of 64 X 36 gm of CHO in that serving = a GL of 23. A low GL is 0-10, high is 20+.  High GL eating patterns are associated with higher risks for diabetes, heart disease, certain cancers and chronic inflammation, which are a significant risk factor for cardiovascular disease.)

To Sum It All Up

We need carbohydrates in our diets. Eliminating carbs altogether is not a good idea because we miss out on important vitamins & minerals and our main energy source. To remain healthy and to either maintain an optimum weight or to lose weight, select the foods with good carbs.

To speed weight loss and to maintain optimum weight, exercise on a regular basis, if not at a gym then at the very least walk every day. Get a pedometer, a little device that counts your footsteps, and set a goal to increase your walking until you reach a minimum steps per day of 10,000.

Eat a variety of fresh fruits, fresh or frozen vegetables, lean protein, dried peas and beans, and good fats such as olive oil, avocadoes and nuts. Limit or avoid prepackaged foods with undecipherable labels, and products with refined flours. Limit or avoid non-100% whole grain pastas, white rice, fruit juices, and white bread. When you reach your target weight you may choose to add more portions per month of some foods. However, if you find that you are gaining weight by increasing the portions or adding certain foods, cut back or avoid them.

The Glycemic Index

The glycemic index (GI) is a numerical system of measuring how much of a rise in circulating blood sugar a carbohydrate triggers—the higher the number, the greater the blood sugar response.  However, the GI is not based on commonly consumed portion-sizes of food.  By using the GI alone, the glycemic effects of foods containing a small percentage of carbs are likely to be overstated, while the glycemic effects of foods containing a high percentage of carbs are likely to be understated.

Introducing the Glycemic Load

The glycemic load (GL) is a way to assess the impact of carbohydrate consumption that takes the GI into account, but gives a fuller picture than does the GI alone.  A GI value tells you only how rapidly a particular carbohydrate turns into sugar.  It doesn’t tell you how much of that carbohydrate is in a serving of that food.  You need to know both things to understand a food’s effect on blood sugar.  That is where GL comes in.  The carbohydrate in watermelon, for example, has a high GI.  But the serving size is not a whole melon, so watermelon’s GL is low.  A GL of 20 or more is high, a GL of 11-19 is medium and a GL of 10 or less is low.

Glycemic Load More Accurate Than Carb Content

Although a low-carb food typically has a lower GI value than a high carbohydrate food, choosing foods purely on the basis of the amount of carbohydrates they contain is less beneficial for blood sugar control and general health than relying on their GL.  Don’t forget, the GL of a food is its GI value per serving, and GL value of a food is the definitive guide to its effect on glucose metabolism and thus blood sugar levels.  Bottom line: choose what carbs to eat on the basis of their GL, not simply their carbohydrate content.  In fact low GL diets have now surpassed low carb diets, as the latter are regarded by most nutritionists as less healthy and less easy to comply with than GL weight loss plans.  The GI value of most foods can be obtained online by searching “Glycemic Index”.  Key Point: when calculating the GL, net carbs are based on Serving Size,  so be sure your are eating the serving size to be the correct glycemic load.

Calculating the Glycemic Load

The GL is easily calculated by multiplying a food’s GI (as a percentage) by the amount of net carbohydrates in a given serving.  GL = GI/100 x Net Carbs (Net Carbs = the total carbohydrates minus Dietary Fiber). The G: gives an indication of how much that serving of food is going to raise your blood-sugar levels.   All food labels list the grams of CHO per serving of a product.  For fresh foods, CHO quantities can be found on many websites.  (A 5 oz serving of white rice has a GI of 64 X 36 gm of CHO in that serving = a GL of 23.)

COMPARING HIGH AND LOW GLYCEMIC LOAD MEALS

LOW GL HIGH GL
FOOD GL GL
1 c steel cut oats 24 1 c inst. oatmeal 51
3 Tb almonds <1 2 Tb raisins 10
6 oz. LF yogurt 10 6 oz. LF yogurt 10
1 sm. orange 4 6 oz. orange juice 10
Tot. Meal GL 2 Tot. Meal GL 17
4 oz. salmon 0 4 oz. salmon 0
1 med swt. potato 17 1 med bak potato 28
1 c broccoli <1 1 c corn 18
1 baked apple 6 1 serv. van wafers 17
Tot. Meal GL 23 Tot. Meal GL 63


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Categories: Carbohydrates, Carbohydrates, Medical Info., Misc. Nutritional Info, Nutrition, Obesity, Weight Management

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  1. Five Tips for Adding More Veggies to Your Meals | Nutrition Health Net - August 5, 2011

    [...] that are packed with more nutrients and more slowly digested carbohydrates. (Go to: “To Carb or not to Carb“, by Donna Hargrove, D.O., F.A.C.O.G, Nutrition Editor of Nutrition Health [...]

  2. The Glycemic Index and Glycemic Load | Nutrition Health Net - November 4, 2011

    [...] index (GI) is a numerical system of measuring how much of a rise in circulating blood sugar a carbohydrate triggers–the higher the number, the greater the blood sugar response.  However, the GI is not [...]

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