Low Carb, No Carb: Do They Work?

From Keto to Paleo to Atkins (remember that one?) many mainstream diets seem to be focusing on carbohydrates. But what are they?

“Carbohydrates can be divided into three groups — starches, sugars and fibers,” said Mary Beth Russell, RD, LN, a registered dietitian at Avera Heart Hospital.

• Starch – found in starchy vegetables like peas, corn and potatoes; beans and lentils; grains, including wheat, oat, barley and rice
• Sugars – found naturally in milk and fruit, and added sugars in processed or packaged foods
• Fiber – in digestible or indigestible forms, found in fruits, vegetables, whole grains, nuts and legumes

Let’s now consider a few things about diets that aim to limit — or eliminate — this part of many foods:

Understanding Popular Diets: Paleo, Keto, Carnivore and Atkins

• The paleolithic or “paleo” diet’s name alludes to that era in time, and it’s based on the idea that we haven’t evolved enough to handle the rapidly changing food industry and our modern diet. Specifics vary, but the general idea is to eat like the hunter/gatherers of the era — fruits, vegetables, nuts and seeds, fish and lean meats, like wild game or grass-fed livestock. Portions and nutrient ratios are not emphasized.
• The ketogenic diet was originally created to help pediatric patients with epilepsy. It’s extremely low in carbohydrate, low to moderate in protein and extremely high in fat. This combination forces the body to use fat for energy and creates ketones as a byproduct. Although recommendations vary, ketosis requires about 75-90% of calories from fat, 5-10% from protein and only 5% from carbohydrate.
• The carnivore diet has become popular in recent years. This diet allows practically zero carbs. You eat meat (mostly red, fatty sources), fish, eggs, butter, organ meats and a few other permissible products. By far, it’s the most restrictive low — or no-carb — option. Scientific evidence and studies still haven’t fully concluded or recognized the health benefits that some people have claimed to experience.
• The Atkins Diet, which may be responsible for launching this low-carb trend, drastically reduces carbohydrate intake to no more than 20 grams per day (in phase 1). It doesn’t require fat or protein monitoring, and while it was not the original design of the diet, many recipes and resources emphasize protein and limit fat. This diet has extremely specific recommendations.

Carbs Are Full of Nutrients, Can Lower Cholesterol

Processed grains like white bread, snack cakes, crackers and such, as well as added sugar have been linked to weight gain and inflammation. On the other hand, whole grains such as brown rice, quinoa and steel-cut oats, along with fruits are linked to a reduced risk from weight gain. The “good” group also serves as great sources of vitamins, which often offer antioxidants to reduce inflammation.

“Carbohydrate is a broad term that includes foods from both ends of the health spectrum,” said Russell.

Good examples are beans and whole grains — they are carbs, but they’re among the best food sources of B vitamins and soluble fiber. Soluble fiber not only helps lower cholesterol, but also helps keep our gut healthy.

Not All Dietary Fats Are the Same

Some studies have shown that the ketogenic diet can increase LDL or “bad” cholesterol. Emphasizing plant-based fats from avocados, nuts, seeds and olive oil will allow the body to stay in ketosis, but reduces the possible impact on heart health.

Risks and Symptoms of Low-Carb Diet

When starting a low-carb diet, many people will complain of lightheadedness, fatigue, headaches, nausea and constipation. These typically are due to the rapid loss of sodium and fluids. Muscle and hair loss also can be side effects when diets are not properly managed. Although rare, ketogenic diets can cause nondiabetic ketoacidosis, a condition where the blood becomes too acidic. In addition to these physical risks, extreme diets increase risk of developing disordered eating behaviors and obsessions.

Research and Hype: We’ve Still Got a Lot to Learn

Nutrition research is hard, but it becomes nearly impossible when you ask participants to follow extremely strict diets for long periods of time. Therefore, the amount of high quality research that focuses on these low-carb diets is limited.

The Best Take-Aways From These Diet Fads

For many people, completely eliminating favorite foods or whole food groups can result in binges and an unhealthy relationship with food.

“A lifestyle which includes moderate amounts of healthy carbohydrates, instead of a low-carbohydrate diet, is likely your best bet for long-term maintenance,” said Russell.

Here are a few tips to enjoy carbs and the benefits they can offer your body:

• Focus on getting nutrient-filled carb sources into your diet
• When making meals, pair carbs with protein and fat to help you feel satiated
• Incorporate favorite carbs and goodies into your diet so you don’t feel deprived
• Try reserving a portion of your day’s carb intake before working out
• If you still want to lower your carb intake, monitor your portion sizes

Of course, talk to your provider before embarking on any dietary changes.