Poliquin

Nutrition Articles


Common (But Harmful) Misconceptions About Low-Carb Diets

by Poliquin Group™ Editorial Staff
8/8/2018 8:24:14 AM

 
The use of low-carb diets is one of the most hotly contested issues in nutrition today. This stems from a combination of factors:
 
  • Everyone responds individually to different nutrition plans, meaning that for some, a low-carb diet isn’t the best choice whereas for others it’s a godsend.
  • Some people don’t like vegetables, which makes it much harder to achieve long-term success with a low-carb diet.
  • When trying to lose body fat, people often look for the easy fix and don’t develop the habits that will make a low-carb diet sustainable.
  • The USDA low-fat, high-carb nutrition guidelines established in the 1970s shaped public nutrition policy such that many misconceptions developed regarding low-carb diets in the medical community.
 
The reality is that if you want to lose body fat or improve your health, a low-carb eating program is an important option. Research shows that low-carb diets tend to produce slightly more fat loss than low-fat diets and they have key cardiovascular and metabolic health advantages that many people can benefit from.
 
For example, reducing your carbohydrate intake has been shown to lower triglycerides (a measurement of the amount of fat in your blood), which is a primary predictor of heart disease. Low-carb diets can also restore insulin sensitivity, improve blood sugar tolerance, and may be an effective treatment for diabetes.
 
Therefore, this article will address some of the more harmful misconceptions about low-carb diets and provide tips for troubleshooting pitfalls.
 
#1: They Aren’t Sustainable
Diets in general are hard to stick to because they go against both our biological realities and the social “food” cues we are exposed to on a daily basis. It’s true that in a high-carb culture in which many people will laugh at the idea of skipping the breadbasket or eating something other than cereal for breakfast long-term low-carb eating might seem like a bit of a stretch.
 
However, if you compare compliance on low-carb with low-fat diets, you’ll find that they tend to be pretty similar. For example, in a comparison of 19 randomized control trials that tested low-carb and low-fat diets, results showed that the average completion rate for low-carb diets was 79.1 percent compared to 77.72 percent for low-fat diets.
 
The difference was small, but this makes it clear that low-carb diets are at least NOT harder to stick to than low-fat diet. If you’ve ever tried a low-carb diet, you know that they convey a few key benefits not present in low-calorie protocols: The higher protein intake has a hunger-reducing effect because protein foods lead to the release of gut hormones that manage appetite. This means that when people lower their carb intake they will automatically decrease their calorie intake without having to intentionally cut calories because they are more satiated.
 
Nonetheless, for many people a low-carb diet isn’t something they do continuously for the rest of their lives. The reality is that in order to achieve lasting fat loss, you need to think about multiple stages that change as you progress.
 
Solution: You might first start with a 2-week low-carb “boot camp” phase in which you eat a very low-carb diet in the 50-gram a day range to restore insulin sensitivity, while creating a calorie deficit with little hunger. After that, you would continue with a low-carb approach but includes a higher carb meal every week in order to replenish muscle carb stores and give yourself a mental break.
 
As body composition improves, you’d focus on honing your training and eating habits, while including healthy higher carb foods in a cyclical manner. For instance, on training days you could eat a higher carb diet, going low-carb on off days.
 
#2: The Only Weight Lost On A Low-Carb Diet Is Water Weight
It is true that low-carb diets lead to a reduction in the amount of water in the body. Glycogen, a storage form of carbohydrates in the muscle that is used to fuel physical activity, contains water. In fact, for every gram of glycogen, you store 4 grams of water.
 
Over the first few days of reducing your carb intake your body burns through your glycogen stores, leading to the loss of water, however, fat loss is also occurring and the combination can give you a mental boost because it leads to a significant decrease in your scale weight.
 
Solution: Rest assured that low-carb diets done correctly lead to plenty of fat loss. If you’re wondering how much body fat you’re losing, get a skinfold test or do circumference measurements around the hip and waist.
 
#3: They Cause Constipation
Low-carb diets require you to reduce your intake of grains, fruit, and starchy vegetables, which results in a drop in fiber intake. Combined with the fact that the body reduces water stores, constipation can occur, especially during the early stages while your digestion is adapting.
 
Solution: Eating low-carb vegetables at every meal and drinking plenty of water should be required for anyone on a low-carb diet. Another factor is that when you start a low-carb diet and insulin levels drop, your kidneys excrete more sodium, which can lead to dehydration. Therefore, getting adequate sodium (2.5 to 3.5 grams) can help. If for some reason you’re not eating vegetables at every meal, try supplementing with psyllium husk dissolved in water or added to a whey protein shake.
 
#4: Ketosis, An Effect Of Low-Carb Diets, Is Dangerous
Assuming your carb intake is low enough (around 50 grams a day), your body will begin to metabolize fat, which leads to the production of ketones.  When you reach a blood level of ketones between 1.5 and 3 mmol/L you are said to be in “ketosis” because your body is burning ketones for fuel instead of glucose.
 
Strangely, ketosis is confused with ketoacidosis even by medical practitioners. Ketoacidosis occurs in uncontrolled type 1 diabetics and it IS quite dangerous, but it is not the same thing as ketosis or low-carb eating. In fact, numerous studies have been done testing the effects of ketogenic diets in a wide variety of population including type 2 diabetics, the obese, strength athletes, and elite gymnasts.
 
Solution: You don’t need to be scared of ketoacidosis when trying a low-carb diet. That said, implementing a ketogenic diet requires a period of metabolic adaptation, which is best endured with the help of an experienced dietitian who can walk you through it.
 
#5: They Cause Bad Breath
On a strict low-carb diet when you are burning body fat and in optimal ketosis, some people have a fruity smell to their breath. The smell is from acetone, a ketone body, and it often reminds people of nail polish remover. For many people, the smell will go away as the body adapts to burning body fat and using ketones for fuel. Some people dislike this smell, in which case there are a couple of solutions, but you should know that it is not the same as the bad breath that is associated with gum disease or gingivitis.
 
Solution: If you’re having a problem with the way your breath smells, the first step is to make sure that the issue IS in fact ketosis and not due to 1) tooth decay, 2) frequent consumption of garlic or onion (both are very healthy but garlic in particular can lead you to release noxious fumes), 3) an unhealthy GI tract (in which case probiotics may help). For overcoming ketosis breath, chewing mint, ginger, or citrus has been reported to help.
 
#6: They Don’t Provide Sufficient Carbs For Brain Function
You’ve probably heard the statement that the brain needs at least 130 grams of carbs a day for it to function properly. Now, it is true that the brain requires a small amount of glucose, but it can also run on ketones. In fact, ketogenic diets developed as a treatment for neurological diseases such as epilepsy because ketones have a neuroprotective effect on the brain. Additionally, many people find cognitive function is enhanced and they are more focused when they are in ketosis.
 
The glucose that the brain requires doesn’t need to come from dietary sources. The body is able to manufacture glucose from other sources, such as gluconeogenesis (protein being turned into carbs) or from lactate.
 
Solution:  A zero carb diet is never a smart move, but as long as you consume around 50 grams of carbs a day, your brain should be just fine once your body adapts metabolically to a low-carb intake This can take a week to 2 weeks and you may feel under the weather—it’s known as the low-carb flu—but it’s worth it because the process means you are metabolically flexible and able to burn body fat effectively.
 
Also, remember that it’s crucial that you individualize your carb intake. Some people will do best on a higher carb intake, whereas others thrive on a low-carb intake.
 
#7: A Paleo Diet Is A Low Carb Diet
It’s kind of funny that the Paleo diet is considered a low-carb diet in most of the mainstream because the reality couldn’t be further from the truth. Analysis of the various dietary practices of our ancestors show the majority are fairly high in carbohydrates, especially root vegetables and fruits.
 
The key is that our ancestors ate zero refined or processed foods. The carbs they ate were often raw, requiring extensive chewing and resulting in a high degree of resistant starch, which is a kind of fiber that promotes the proliferation of anti-inflammatory bacteria in the gut.
 
Solution: Whether you adopt a low-carb way of eating or not, the key isn’t to eat in way that fits a label. Don’t get distracted by nutrition dogma or marketing. Work on cultivating your body by exercising and eating in a way that makes you look and feel good.
 
#8: Low Carb Diets That Are High In Protein Are Bad For Your Bones
This misconception came about due to the fact that a higher protein intake increases levels of calcium in the urine, which was incorrectly interpreted as being bad for bone density. But studies don’t support it. Pretty consistently, the higher your protein intake, the stronger your bones will be. Additionally, people with a higher protein intake have lower risk of fracture.
 
Solution: The one thing you should be doing when eating a lot of protein is to decrease your acid load by eating plenty of vegetables and other antioxidant-rich foods such as berries. This will minimize calcium excretion in the urine, while also countering inflammation that can occur if you eat a high protein intake without sufficient fiber.