What Is A Low-Carb Diet?

Many people don’t realize it, but there are lots of low-carb diets other than keto.

In fact, the granddaddy of all low-carb eating plans, the Atkins diet, is still going strong after nearly 60 years. It was viewed as a “fad” diet until fairly recently, when research confirmed the relative safety and effectiveness of low-carb diets.

Today, most experts agree that restricting carbs can be more effective for weight loss than restricting fat intake. There’s also a good deal of research showing that a healthy low-carb diet can help lower blood pressure, bad cholesterol levels and the risk of heart disease.

That’s why low-carbohydrate diets are so popular. But why are they so effective?

Carbs and the Diet

Let’s start with the obvious. The body needs energy to function, and that energy comes from the food we eat. More specifically, it comes from glucose, the form of sugar that’s created when starches in our diet (primarily complex carbohydrates like flour and beans) are broken down during digestion.

That causes two things to happen. Glucose enters the bloodstream as blood sugar, and the body releases insulin to help cells absorb the blood sugar. There’s one problem with that process: insulin also encourages the production and storage of body fat.

So the more carbs you eat (especially if they’re “bad” carbs), the more insulin there is in your system and the more fat you put on. Placing some restrictions on carbohydrate consumption, on the other hand, lowers insulin levels and prevents weight gain. Even better, a low-carb diet reduces the amount of available glucose, encouraging the body to burn stored fat instead of glucose for stored energy.

There’s one other benefit. Dropping most carbs from your diet means you’ll be eating more protein instead, and protein is going to fill you up quickly since it doesn’t contain empty calories. You’ll feel full and eat less on a low-carb diet.

The quick summary: when you eat fewer carbs, and stay away completely from the worst ones like bread, pasta, sweets and junk food (which are all loaded with complex, refined carbohydrates), you’re going to lose weight.

Is That Why the Keto Diet Works?

Sort of. Keto and low carb both use the same basic principles, but the keto diet takes them a step further. On keto you cut your carb intake so low that the body can’t produce any glucose at all. Since the body still needs energy, it immediately starts burning stored body fat, and does it efficiently – because the process creates molecules known as ketones, which the body can use as an alternate energy source.

If you’ve ever heard the term “ketosis” in conjunction with the keto diet, that’s what people are talking about. Ketosis is the name for the metabolic state the body enters when it starts using ketones instead of glucose for fuel. In ketosis you burn stored fat extremely quickly, which is why the keto diet is known for producing rapid weight loss.

It’s also known for its major restrictions on what you can eat, and some people can’t tolerate those restrictions. Others bail out when they’re hit with the extreme fatigue and other side effects known as the “keto flu,” which usually hits during the first week of ketosis.

Keto isn’t the only choice, though. There are other low-carb diets which aren’t quite as drastic but still help you lose weight.

Low-Carb Diet Choices

We’ve already mentioned the Atkins diet, which is based on the original book published by Dr. Robert Atkins back in 1972 and has been refined since then.

There are many other variations on low-carb eating plans, and the big difference between them is usually how many carbs – or what type of carbs – you can eat. These diets are the most common.

Standard Low-Carb Diet

Many dietitians describe any eating plan that includes less than 100 grams of carbs per day as “low-carb.” In effect, that simply means you’re eating fewer carbs than you normally would, without any specific restrictions. Most of these variations focus on lowering consumption of complex carbs like grains and sugar; many also suggest limiting starchy vegetables like potatoes or some fruits.

Generally speaking, a diet with 50-100 grams of carbs per day is suggested for slow dieting or weight maintenance, while lower than 50 grams can produce faster but steady weight loss. By contrast, keto limits you to about 20 grams per day.

Atkins Diet

Standard Atkins consists of four phases. You start by eliminating most carbs during the first week (known as the induction phase), so you’re only consuming 20 grams per day. You then add in more and more healthy carbs each week as you lose weight, until you reach your goal and stay in a continuing lower-carb maintenance phase.

A variation on this diet is known as Eco-Atkins, a vegan version of Atkins in which you can eat more healthy carbs, but focus primarily on plant-based proteins and fats.

Paleo Diet

The Paleo diet has received almost as much attention as keto in recent years. It’s based on the idea that our bodies weren’t meant to survive on all of the processed foods we now eat – and calls for a return to what our Paleolithic ancestors ate when they were cavemen (thus the other name for Paleo, the caveman diet).

The basic diet specifies that only whole foods can be eaten; no dairy, grains, sugar or processed foods are allowed. But there’s a low-carb version of Paleo, which also eliminates natural starches like potatoes and high-carb fruits (almost everything except berries, peaches and a few others).

Mediterranean Diet

Experts have called the Mediterranean diet one of the healthiest options and one of the best choices for weight loss. It emphasizes the types of foods eaten in countries like Greece and Italy, which have startlingly-low levels of heart disease and other common illnesses.

Whole grains, vegetables, fish, seafood and olive oil are the building blocks of the Mediterranean diet, with red and processed meats, sugar, refined grains and oils, and processed foods mostly or completely eliminated. There’s an effective low-carb version of this diet as well, which cuts out foods like whole grains and high-carb fruits.

Other low-carbohydrate diets include commercially-inspired ones like Whole30 (similar to Paleo, but without natural sugars like maple syrup and honey) and the South Beach Diet (a phased eating plan, but with less fat than keto or similar diets). Some people also advocate a “zero-carb” diet with no carbs at all, but it’s believed to be a risky choice due to its lack of many basic nutrients.

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