Hello there, and welcome to my podcast. This is your host, Sangeeta Pradhan. I’m a Registered Dietitian, Certified Diabetes Educator and a member of the Academy of Nutrition and Dietetics.
The goal behind my podcast today is to bring carbohydrates from whole grains back into the spotlight and highlight their numerous health benefits. Along with whole grains, we will also talk about the scientific facts regarding carbohydrates, separating them from the science fiction and misguided notions shall we say, that surrounds the topic of carbohydrates today.
If you are like any other consumer, you are probably at least somewhat confused as to whether you should avoid carbs or fats and just follow the ever popular high protein diets, that your co-worker perhaps or perhaps your best friend, may be following today. In fact, have you noticed how the popularity of the macro-nutrients in our diets, carbs, proteins and fats seems to ebb and flow like fashion statements almost, with carbs all the rage in the 90’s and now out of favor like dietary outcasts, wouldn’t you say- while proteins on the other hand have been idolized by the popular press! Oh, and I’m sure the gluten free mania that appears to be gripping the nation today must leave at least a few of us bewildered and wondering if we should also be jumping on that bandwagon ??!
So in order to shed some light on this somewhat confusing topic, let me share a few scientific facts regarding carbs starting with their functions.
Fuel source: For starters, carbs are a fuel source. Think of carbs as your body’s energy currency, your body’s primary fuel source. So essentially carbs are to your body what fuel is for your car. Your car does not run on an empty tank-wouldn’t that be nice, and neither can you! This means that carbs are not the dispensable macro-nutrient that our popular culture would have us believe. That said, just like the fuel at your local gas pump, choose “premium” or superior quality carbs over “regular” every time if you wish to get the most “mileage” out of your body, no pun intended, and I would try not to “overfill”.
So what are premium carbs? Whole and unprocessed carbohydrates from whole grains, legumes, fresh fruits and vegetables, would be considered premium carbs. Whole grains are intact grains. These intact whole grains have an outer layer called bran which is rich in fiber, there is an inner germ layer that is chock-full of nutrients such as Vitamin E, phytonutrients and minerals, and if you think about it, that makes sense as the germ happens to supply food to the little, growing sprout. There is also a starchy endosperm between these 2 layers, and it is this endosperm that gets converted to glucose or sugar as we know it, for energy.
After processing, whole grains should retain the same proportion of the bran, germ, and the endosperm as that of the original grain to be considered whole grains.
Well, as you may know, today’s grains unfortunately, are pulverized in a mill in a manner that strips the fiber and nutrient rich bran as well as the germ, leaving behind the starchy endosperm only and a super fine white flour. So what’s the big deal? Well, when you are dealing with fine white flour, it creates a greater surface area for your digestive enzymes to work on, leading to a rapid breakdown of the available carbohydrate to sugar or glucose, this in turn then sends a signal to a gland in your body known as the pancreas. The pancreas as a natural response, then releases a proportionately large amount of insulin, leading to a sugar “crash”, prompting hunger pangs, an all too familiar phenomenon, unfortunately that I think may of us may be able to relate to.
So even though many grains are “enriched” by adding back several B vitamins (such thiamine, riboflavin, niacin, and so forth), a key component, fiber is typically not added back to enriched grains. Thus, the stripped down, refined grain that we are eating today is all but the pale shadow of that hearty, wholesome grain that our ancestors used to eat!
And guess what, it is these refined grains that may have given most all carbs a bad rap. In our quest to avoid the undesirable carbs, some of us may have mistakenly turned our backs on the healthful whole grains, chock full of nutrients and high in fiber, and in so doing, we just may have thrown out the baby with the bath water! The takeaway here is that the quality of carbs is key, and clearly all carbs are not created equal!
Protein-sparing action of carbohydrates: Switching gears a little bit, let’s look at something known as the “protein sparing action of carbs”. So what’s that all about? Well, the “protein sparing” effect of carbs simply means that when carbohydrates are consumed in adequate amounts, it enables your body to use protein for what it’s meant to be used for- i.e., as building blocks and to help with the growth, repair and re-building of cells in your body, rather than for energy. As we just discussed, your body’s primary energy source is carbohydrate, not protein. However only an adequate amount of dietary carbs (and to a lesser extent, dietary fat), can prevent the use of protein for energy, and their action in doing so is called the “protein sparing” effect of carbs. Essentially this simply means that you would need to consume at least 50-100 grams of carbohydrates per day depending upon the individual to prevent proteins from being used for fuel. Just in case you are wondering what that translates to in terms of real food, 50 grams of carbs would amount to 2 slices of bread, a small fruit and ½ a cup of cooked vegetables or perhaps, a cup of oatmeal a glass of milk and a cup of salad, and that would be it. You can see how restricting carbs to that extent realistically, is just not sustainable for most of us.
In this same context, let’s talk about a condition called ketosis that some of you may be familiar with. When some folks follow extreme diets with limited amount of carbohydrates, your body then uses fats as a secondary or back up fuel source. Remember as we discussed before, carbs are your primary fuel source, but when we follow extreme diets, your body then has to use fat as the secondary or back up fuel source. However, what’s interesting is that fats burn incompletely when there are limited amounts of carbs, and this leads to the production of compounds known as ketones. Ketosis is simply a condition when large amounts of ketones build up in your blood which could then shift the natural acid base balance in the body. However, when you follow a balanced diet, with the right proportions of carbs, proteins and fats, which is typically about 50% of your calories coming from carbs, roughly 15-20% from protein and approximately 30% from fats, it is very unlikely that your body would go into a state of ketosis. It is the extreme low carb diets, or with extreme calorie restriction, that the body may shift to a state of ketosis.
Fiber rules!: Finally, carbs are an important source of fiber in our diets. Fiber is the structural part of the plant and is derived exclusively from carbohydrate rich foods such as whole grains, legumes, fruits, vegetables and nuts. Although fiber is the part of the plant food that you cannot digest, ironically, it is just as important as the part that you can!
Ever notice that a bowl of oatmeal with some fruit seems to hold you much longer than that giant bagel that you may have perhaps picked up from your neighborhood cafe? The higher fiber content in the oatmeal and fruit simply means that your body has to work harder at breaking down the carbs in those foods, causing a slower rise in sugar in your blood, a proportionately smaller amount of insulin from your pancreas, preventing hunger pangs later. When it comes to the bagel though, the refining process strips it of fiber, thus enabling your body to digest and absorb the carbs from the bagel rapidly, leading to spikes in sugar, large amounts of insulin, a subsequent sugar crash, setting off the all too familiar “snack-attack” that we discussed earlier. The other interesting fact about fiber is that it can also help lower cholesterol, makes you feel full, which certainly helps with weight loss, and there are certain forms of fiber that can actually feed the good bacteria in your gut, promoting overall good health and optimal gut health as well.
In fact there are numerous studies demonstrating the health benefits of fiber and whole grains. These studies show that the intake of dietary fiber and whole grains is inversely related to obesity, type two diabetes, possibly cancer and cardiovascular disease. In other words, as we up our whole grain and fiber intake, we see a smaller incidence of these chronic diseases
Well, now that you have an understanding of all that whole grains and “premium” carbs bring to the table, let’s look at what it takes to actually get these products to our dining table, literally! To do so, please read my post: “Whole grains and fiber:Unraveling the puzzle”, on my blog, Web dietitian. Thank you, and stay tuned!