by Charles Poliquin
De-emphasizing carbohydrates in a diet tends to lead to greater fat loss and better health for more people than higher carb, lower fat eating styles. This article will make the case for lower carb diets.
You’ve heard the statistics: At least a third of Americans are obese and two-thirds are overweight. These rates are increasing.
Diabetes rates are even more alarming because vast numbers of people are thought to have undiagnosed diabetes. In the U.S., nearly 10 percent of Americans have diabetes and about 25 percent are pre-diabetic with deranged insulin health and too much body fat.
Carbohydrates, fat, overeating, and inactivity have all been blamed for the obesity and diabetes epidemics, either in combination or alone.
Interestingly, the U.S. government used to recommend that people eat high-carb diets nearing 300 grams of carbs a day. However, in the 2010 dietary guidelines, the USDA radically reduced carb recommendations to 130 grams for adults, but still suggests a fairly large proportion of the diet be from carbs (45 to 65 percent of calories).
Is the USDA making a case for a low-carb intake?
Either way, reducing dietary carbs is not a passing dietary fancy. It is a viable lifestyle for leanness and well being. A boatload of scientific research over the past decade informs these eight compelling reasons to choose a lower carb diet.
#1: Lose fat. Lower carb, higher protein diets help you lose fat and keep it off by preserving muscle.
Lower carb diets done the right way are extremely effective for reducing body fat for the following reasons:
There is a hierarchy to the thermic effect of food, or the amount of calories it takes the body to digest protein, carbs, and fat. Protein elicits the highest calorie burn, followed by carbs, and then by fats.
Second, less carbs means you eat more protein that is satisfying and preserves muscle mass so that you burn more calories overall. The amount of calories your body burns at rest is proportional to your overall body weight and more influenced by muscle than fat because lean tissue burns more calories than fat tissue.
Preserving muscle mass is the vital difference between maintaining fat loss and experiencing rebound fat gain. The effect is seen in a noteworthy 21-day study that restricted energy by 30 percent in lean participants.
Compared to a diet that allowed the U.S. RDA of protein of 0.8 grams per kg of body weight, a diet that replaced carbs with protein so that subjects consumed 1.6 grams/kg of protein a day was found to preserve lean mass, while preferentially producing fat loss.
Seventy percent of the weight lost in the 1.6 g/kg of protein group was body fat and they only lost 0.8 kg of lean tissue, whereas only 41 percent of the weight lost was fat in the 0.8 g/kg of protein group, and they lost 2.3 kg of lean mass. This loss of lean mass reduced the subjects’ daily energy expenditure dramatically.
Use It: Eat real whole foods and individualize your carb intake. A review in the American Journal of Clinical Nutrition suggests that in an overweight, minimally active population, less than 50 grams of carbs a day is ideal for fat loss.
Up to 150 grams of carbs a day is recommended in leaner more active people, whereas those doing intense training (speed and power field sports or combat training) may benefit from higher carbs. Cycling carbs is another option in which training days are higher carb and rest days are very low carb.
#2: Eat fewer calories. Lower carb diets reduce food cravings and hunger.
Carbohydrate foods are composed of sugars, which is why they tend to be sweet in taste. In humans, the sweet sensation stimulates food intake, especially when combined with fat.
There’s an evolutionary theory that humans are programmed to crave and seek out energy-rich sweets that are higher in fat and calories in order to put on body fat so that they will have energy stores during times when food is scarce.
Many studies show we behave accordingly: Anytime we eat sweet foods, our appetites are stimulated and we end up eating more calories even if those foods are sweetened with artificial sweeteners.
Stop overeating by limiting your carb intake. You’ll avoid gaining body fat and the unfortunate metabolic changes relating to hormone balance and insulin health that occur from a chronic overload of blood sugar.
Use It: Develop a taste for vegetables and lower glycemic fruits because these carbs are well known for reducing food intake and cravings. Use olive oil, coconut oil, butter, vinegars, spices, and other flavorful condiments to enhance flavor and variety of vegetables and fruits.
#3: Reduce diabetes risk. Low carb eating is most favorable for metabolic health when it is based on whole plant-based carbs that are high in indigestible fiber.
Fiber plays a massive role in allowing you to avoid hunger and reduce diabetes risk. But most people who pay attention to fiber’s importance don’t understand that only certain types of fiber have a relevant beneficial effect.
Insulin and blood sugar are regulated by the rate of digestion and the amount of fiber a food contains. Certain carbs that are high in undigestible fiber, such as plants, decrease energy intake due to slower digestion compared to those that are quickly digested and low in this type of fiber.
But, processed foods with added fiber, or foods that naturally contain digestible fiber, don’t have this benefit and don’t reduce food intake. And it just so happens that those are the foods that humans like to eat.
You can see the profound influence of intact fiber in a study that tested the effect of eating an apple, apple puree, or apple juice. Results showed that insulin was highest after participants drank juice, followed by the puree, but lowest in response to the whole apple. The scientists concluded that removal of fiber led to the following ill effects:
• faster and easier ingestion,
• decreased satiety,
• disturbed blood sugar,
• inappropriate insulin release,
• stimulated hunger and overeating
The long-term effect of consuming juice compared to whole fruit was recently documented in a survey of 187,382 people that found that those who drank fruit juice daily increased their risk of developing type 2 diabetes by 21 percent. Those who ate at least two servings of whole fruit—grapes, apples, and blueberries—decreased risk of type 2 diabetes by 23 percent.
Use It: Favor whole, low-glycemic complex carbs. Examples are berries, cherries, grapes, plums, peaches, and citrus, and all veggies (be conservative with potatoes and sweet potatoes).
Avoid simple carbs, foods with artificial no-calorie sweeteners, and high-glycemic complex carbs. Examples of these foods include bread, pasta, crackers, foods with added sugar, soda, diet soda, juice, sports drinks, cookies, cake, cereal, and grains.
#4: Take control of what you put in your mouth. De-emphasizing carbs in favor of protein allows you to avoid the pitfalls created by a medical community that is ignoring the facts.
If you replace carbs with protein and “good” fats, you can improve meal satisfaction, and improve metabolic health. For every 1 percent increase in protein, people naturally decrease calorie intake by between 32 and 51 calories daily.
This is well documented. Unfortunately, the medical and nutrition communities are extremely reluctant to advocate reduced carb eating plans. A scientific analysis of diets to treat diabetes suggests the poor view by the medical community of low-carb diets is due to the following elements:
First, there is backlash against the Atkins diet that allows for unlimited fat intake. Health organizations take a literal interpretation of the free for all of dietary fat, fearing that people will go overboard on fat.
In reality, scientific-controlled diets that are high in protein and fat and allow subjects to eat to their liking tend to lead to a reduction in total calories due to their hunger-reducing nature.
Second, the mainstream medical community argue that weight loss on low-carb diets is attributed to loss of body water as muscle glycogen stores are reduced. Over the first few days on a low-carb diet this is true, but after 2 to 3 weeks, active fat loss occurs and has been documented over and over and over again in research trials.
Third, high-carb intake in conjunction with a high-fat intake leads to markedly poor body composition, elevated triglycerides, an inflammatory state, and increased cardiovascular disease risk.
Use It: Identify a macronutrient distribution that allows you to consume your ideal calorie intake without having to obsessively restrict portions. You should feel satisfied after eating and be able to avoid food cravings and constant hunger on your eating plan.
#5: Don’t be a slave to carbs. Lower carb diets require metabolic flexibility for better athletic and brain performance.
Reducing carb intake in favor of fat improves the body’s ability to burn fat for energy. This is a state of “metabolic flexibility” or “fat adaptation.” Being metabolically flexible has a neuroprotective effect on the brain and decreases oxidative stress that comes from a higher carb diet.
One of many problems with living off carbs is that you have to continually eat them every few hours in order to maintain blood glucose levels. It’s not a very efficient way to fuel the body and it inhibits fat loss.
Use It: There are two methods of adapting the body to burn fat readily: First, reducing carb intake in favor of protein and fat has been shown to increase fat oxidation in lean people. Second, performing high-intensity training (HIT) such as sprint intervals has been shown to increase fat burning in both lean and overweight subjects.
For overweight, sedentary people, doing HIT training is the catalyst to improve metabolic flexibility, whereas altering diet alone does not appear to be effective in the short term.
#6: Prevent constant hunger and leptin resistance. Strategic lower carb diets improve leptin sensitivity to prevent hunger and enhance sleep.
Leptin is a hormone that is secreted by fat tissue a few hours after insulin is elevated, and it reduces hunger sensations. Working properly, higher body fat will mean higher leptin levels and less hunger. This will allow for either maintenance or reduction of body fat. Low body fat means lower leptin and more hunger.
But this seemingly effective physiological system for weight management can go wrong easily. When people chronically overeat, or eat too many carbs, insulin is continuously being spiked and the body’s cells becomes resistant to insulin.
This leads to more insulin secretion, which causes more leptin secretion. Over time, this causes the hypothalamus of the brain to become resistant to leptin’s message to reduce hunger.
Night eating also dysregulates our response to leptin, so if sleep is an issue for you, it’s important that you adopt a diet and meal frequency that optimizes insulin and leptin sensitivity.
On the other hand, insulin and leptin can also get out of whack with long-term very low-carb diets. The absence of insulin release due to massive carb restriction leads to no leptin release. This is why some form of carb cycling can be beneficial.
Use It: Low-carb doesn’t mean no-carb. Including some complex carbs in your diet is indicated to signal the hypothalamus to hit the leptin reset button so your metabolism doesn’t become resistant to fat loss. Carb cycling is another option that has also been shown to support the metabolic hormone cascade.
#7: Reduce blood pressure. Reducing carbs in favor of higher protein intake can lead to meaningful reductions in blood pressure.
Research shows that high-protein, low-carb eating can reduce blood pressure much more than the average seen with blood pressure lowering drugs of between 0.8 and 2 mm. One study found that hypertensive subjects reduced systolic readings by nearly 5 mm Hg due to replacing carbs with protein.
The effect appears to be due to improved body composition and better insulin sensitivity. Fat loss of 1 kg tends to equal a decrease in blood pressure of 1 mm Hg. In addition, a high-protein diet is thought to improve the overall function of blood vessels, allowing them to dilate and decrease pressure more effectively.
Use It: The beauty of a lower carb diet is that you can make significant changes in blood pressure by replacing carbs with protein without having to reduce your calories or the amount of food you eat. Start slow by replacing 30 grams of carbs with protein, eventually increasing to 60 grams.
#8: Reduce cardiovascular disease risk. Lower carb intake improves cholesterol, triglycerides, and reduces inflammation.
A mounting body of evidence shows that the traditional low-fat, high-carb diet is associated with cardiovascular inflammation and hardening of the arteries. Elevated triglyceride levels, which lead to cholesterol problems in the long run, are observed in as few as five days with higher carb, lower fat diets.
Conversely, low-carb diets have been consistently shown to improve cholesterol markers, even in the absence of weight loss. When low-carb diets are paired with physical training so as to produce loss of body fat, the beneficial effect for cardiovascular health is even greater.
This may be confusing because health policy has been telling you for years that saturated fat elevates cholesterol, however, a commentary published in the journal Nutrition and Metabolism explains that cholesterol markers are worsened the most by eating high-carb diets.
This negative effect is exacerbated when simple carb intake is combined with “isolated” vegetable fats. Reducing carb intake and replacing isolated fats such as corn, soybean, canola, and vegetable oil with naturally occurring animal fats improves the cholesterol ratio, reducing heart disease risk.
Use It: Avoid simple carbs in favor of complex carbs that are low-glycemic. Eliminate isolated vegetable fats, such as the cooking oils mentioned above. Opt for butter and coconut oil for higher heat cooking because they are not oxidized. Use olive oil for salad dressing and lower heat cooking (it is easily oxidized at high temperatures, producing toxins).
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