Carbohydrates 101
Carbohydrates, better known as carbs, have been villainized in the media on several levels. Just as fat was the scapegoat for a culture of overindulgence in the 80s and 90s, now carbs have become the primary suspect. And just as the information about fats was proved to be filled with half-truths and marketing gimmicks, we now see the same with carbs. A common misconception about carbs is gluten. Gluten is wheat protein and has nothing to do with carb load. So just because something is gluten-free does not inherently mean that it is low-carb. The results of high-fat vs high-carb diets for weight loss have not been clear and are wildly debated. There is also still debate over how carb dominant vs. fat-dominant diets affect athletes, mainly due to the difference in metabolic needs for each sport. There has been very little evidence that shows very low-carb diets (<20% of total calories) will cause more body fat loss than an equal calorie diet containing a normal carb load(40-60% of total calories). Although low-carb, high-protein diets have shown some potential for weight loss, these diets are not as beneficial for athletic performance. There is also some truth to some of the statements made in the media about carbs. Over-consumption of processed sugars has been proven to be linked to diabetes, especially Type 2. Diets consisting of very high carbs (>70% of total calories) have been shown to increase body fat in sedentary individuals more so than normal carb-load diets. What has been shown time and time again is carb intake before, during, and immediately after training or participating in competition increases overall performance. Current literature recommends an intake of 8-12 g/kg of body weight to maximize glycogen stores in the days leading up to max effort training or competition, therefore increasing performance potential. An intake of 1-2 g/kg of body weight immediately after training or competition is essential to optimize and enhance recovery for any individual. So before cutting carbs to lower levels, make sure total calories is in an acceptable range (1200-1800 per day typically for weight loss, up to 10,000 per day for professional athletes and Olympians, so normal is a relative term depending on your status), and the diet has a balance of roughly 50% Carbs, 25%Protein, and 25% Fat. If the results are still elusive after 12 weeks of proper exercise and diet, then further tuning of the diet will be needed.
Carbs come in all different varieties, and with these varieties come individually specific effects on the body. Luckily, the glycemic index and the glycemic load were created to help people choose what carb sources are best for them. The glycemic index (GI) is an indication of how a carb affects blood sugars, with values ranging from 1-100. Even higher values are given to foods that cause extreme blood sugar spikes. Low GI foods like pasta or apple have values ranging from 1-55 and have a low impact on blood sugars. This is important because having sugar spikes consistently over long periods of time decreases insulin sensitivity, which leads to health problems such as diabetes and cardiovascular disease. These low GI foods should make up the majority of carb intake, as they help regulate blood sugars and are a consistent source of energy. Moderate GI levels are valued from 56-69 and include foods such as rolled oats or sweet potatoes. Although they have less impact on blood sugars than high GI foods, these should still be ingested with less frequency than the high GI carbs. High GI carbs are the reason carbs have gotten such a bad rap. These carbs spike blood sugars, causing periods of increased energy and alertness, followed by a crash due to the body overcompensating for the sudden increase. These foods include many cereals, bread, and white starches like white rice or potato. High GI foods can be very useful around workout time and should be used readily for those training at an advanced level. However, if weight loss is the primary goal, it is recommended that these carb sources are used sparingly. It should be noted that fiber is a non-impact carb, which means it carries no nutritional value. The body cannot process fiber, so the impact on blood sugars is non-existent. So when totaling up daily carb intake, fiber should be taken out of the total grams of carbs. Glycemic load (GL) is an indication of how long a food will impact blood sugar levels. It takes into consideration the GI and the number of carbs in a given serving. To calculate GL; GL= GI x (Net Carbs/100). So for example, a watermelon and a doughnut have roughly the same GI (approximately 75), however, there are only about 11g of carbs in a serving of watermelon, while there is upwards of 30g in a doughnut. This translates to the doughnut having a longer effect on raising blood sugars and the insulin response associated with that rise. So when choosing the right foods, don’t forget to take the GI and the GL into consideration, focusing on Low GI to minimize blood sugar spikes.
