Carbs, Sugar, And Keto: What's The Difference?

Carbohydrates, or carbs, are one of the three essential macronutrients that the body needs to function. They are a vital source of energy, providing the body with the fuel it needs. Carbohydrates are made up of sugars, which get their name from their chemical composition: carbon, hydrogen, and oxygen. The length of the sugar chain making up the carbohydrate determines the rate of digestion and absorption.

There are two basic types of carbs in food: starches and sugars. Starches are made up of long chains of individual glucose (sugar) units that are linked together. Sugars are much shorter chains and are found in whole foods such as many plants and dairy products.

When following a keto diet, it is important to restrict carbohydrate intake. However, not all carbohydrates are the same, and not all of them are bad. Complex carbohydrates, such as whole foods that are high in fiber and nutrients, can provide added nutritional benefits and make us feel fuller for longer. On the other hand, simple carbohydrates, which are found in processed foods, are digested faster and have been implicated in weight gain and metabolic diseases.

To stay in ketosis, it is recommended to consume 20 or fewer grams of net carbs per day. Net carbs are calculated by subtracting dietary fiber and certain sugar alcohols from the total grams of carbohydrates in a given food. Dietary fiber is not broken down and absorbed by the digestive tract, while sugar alcohols are only partially digested and absorbed.

The keto diet is high-fat, moderate-protein, and very low-carb

The ketogenic, or keto, diet is a high-fat, moderate-protein, and very low-carb eating plan. It is well known for its short-term weight loss effects, but it is originally a therapeutic diet used to control seizures in people with epilepsy.

On the keto diet, 70% to 80% of your calories should come from fat, 15% to 30% from protein, and 5% to 10% from carbohydrates. This means that, in a 2,000-calorie diet, you would be consuming approximately 165 grams of fat, 75 grams of protein, and 40 grams of carbs. However, the exact ratio depends on your particular needs.

The keto diet is very different from traditional low-carb diets. While low-carb diets recommend getting 30% to 40% of your calories from fat, keto requires you to consume almost twice that amount. The keto diet also restricts carbohydrates more than a low-carb diet, allowing only 5% to 10% of your calories from carbs, compared to the 10% to 25% recommended in low-carb diets.

On the keto diet, it is important to consume healthy unsaturated fats, such as nuts, seeds, avocados, tofu, and olive oil. However, it is also encouraged to consume high amounts of saturated fats from oils, lard, butter, and cocoa butter. Protein is also a part of the keto diet, but it is important not to consume too much, as it can interfere with ketosis.

The keto diet is not just about consuming high amounts of fat; it is also about significantly restricting carbohydrates. This means eliminating most fruits, dairy, whole grains, legumes, and even some vegetables. It is recommended to get your carbohydrates from leafy greens, such as kale, Swiss chard, spinach, cauliflower, broccoli, and asparagus.

While the keto diet can be effective for short-term weight loss, it is not necessarily a healthy long-term dietary choice. It can lead to an increased risk of heart disease due to the high levels of saturated fat. Additionally, the restrictive nature of the diet may lead to nutrient deficiencies, especially if you are pregnant, lactating, or have complex health conditions.

Before starting the keto diet or any restrictive diet, it is important to consult with a doctor or registered dietitian to ensure it is safe and suitable for your individual needs.

Carbohydrates are a vital source of energy for the body

Sugars make up a large part of carbohydrates. Their name comes from their chemical composition: carbon, hydrogen, and oxygen. The length of the sugar chain making up the carbohydrate determines how quickly it is digested and absorbed.

Monosaccharides, often referred to as single sugars, are the building blocks for larger, more complex carbohydrates. Glucose and fructose are examples of simple sugars. Disaccharides, meanwhile, consist of two chemically joined sugar molecules, such as sucrose, a combination of glucose and fructose.

Complex carbohydrates are made up of more than two sugar molecules. They can be split into two categories: oligosaccharides and polysaccharides. Oligosaccharides are short chains, usually between 3 and 10 sugar molecules long, while polysaccharides are long-chain carbohydrates that may contain hundreds or even thousands of monosaccharide units.

The human body's main source of energy is carbohydrates. However, they have also been blamed for the rise in obesity, metabolic syndrome, and cardiovascular disease. But not all carbohydrates are created equal. It is processed and refined carbs that have given all carbohydrates a bad name. These carbs have had all their fibre and essential nutrients removed, so they can be broken down into glucose and released quickly into the bloodstream, causing a spike in blood sugar levels.

Rather than eliminating all carbohydrates, it is better to think about the quality and quantity of the carbohydrates consumed. Cutting down on added sugar is beneficial, but complex carbohydrates such as fibre, polyphenols, and essential vitamins and minerals are important for health.

The brain relies on glucose as its primary energy source. Research has shown that drinking a glucose drink can improve the episodic memory of both children and adults who have not eaten.

It is added, refined sugars in processed foods that are a health risk, not the natural sugars found in fruit, vegetables, and milk. Most individuals consume more added sugar than the recommended amount. A soft drink with lunch and a chocolate bar for a snack are often enough to exceed the daily limit.

The human brain is powered by glucose

The human brain is highly dependent on glucose as its main source of energy. Glucose is a form of sugar, and the brain is the most energy-demanding organ in the body, using half of all the sugar energy. Glucose provides the fuel for physiological brain function through the generation of ATP, the foundation for neuronal and non-neuronal cellular maintenance, as well as the generation of neurotransmitters.

The adult human brain, at rest, consumes approximately 20-25% of the body's total glucose consumption. However, the developing brain requires an even greater percentage of glucose. Studies indicate that glucose consumption in the brain is highest during childhood, reaching about twice that of the adult brain per gram of brain tissue. This is due to the rapid synaptic proliferation occurring in the brain at this time.

Brain functions such as thinking, memory, and learning are closely linked to glucose levels and how efficiently the brain uses this fuel source. If there isn't enough glucose in the brain, neurotransmitters, the brain's chemical messengers, are not produced, and communication between neurons breaks down. Hypoglycemia, a common complication of diabetes, can lead to a loss of energy for brain function and is linked to poor attention and cognitive function.

The effects of glucose on the brain are profound in diabetes, where persistently high blood glucose levels can affect the brain's functional connectivity and brain matter, causing atrophy and small-vessel disease, which restricts blood flow in the brain.

Refined carbs and sugar are linked to obesity, diabetes, and heart disease

Refined carbohydrates and sugar are linked to obesity, diabetes, and heart disease. This is due to their impact on blood sugar levels and insulin resistance, which can lead to weight gain, elevated blood pressure, and increased risk of cardiovascular events.

Refined carbohydrates are simple sugars and starches that have been processed, removing fibre and other essential nutrients. They are quickly digested and absorbed, causing a rapid increase in blood sugar levels. Sugar, a simple carbohydrate, is often added to processed foods and beverages, making it easy to consume excessive amounts. High intake of refined carbohydrates and added sugars can lead to weight gain and insulin resistance, increasing the risk of type 2 diabetes.

Additionally, the immediate post-meal spikes in blood glucose and triglyceride levels caused by refined carbohydrates and sugar contribute to oxidative stress, inflammation, and endothelial dysfunction. These factors are directly linked to the development of type 2 diabetes, hypertension, and cardiovascular disease. The risk is particularly pronounced in individuals with a genetic predisposition to insulin resistance and metabolic syndrome, such as South Asians.

Furthermore, a diet high in refined carbohydrates and added sugars is associated with an increased risk of non-alcoholic fatty liver disease (NAFLD). NAFLD is a significant risk factor for cardiovascular disease and is prevalent among individuals with a sedentary lifestyle and a diet high in sugar and refined carbohydrates.

To reduce the risk of obesity, diabetes, and heart disease, it is essential to limit the consumption of refined carbohydrates and added sugars. Prioritising whole grains, complex carbohydrates, and natural sources of sugar can help mitigate these health risks.

Complex carbs are good for the gut microbiome

Carbohydrates are the body's main source of energy. They are made up of starches and sugars. Starches are long chains of individual glucose (sugar) units, while sugars are much shorter chains. Starchy foods generally don't taste sweet, but they are broken down into glucose in the gut, which raises blood sugar levels. Sugars are found in whole foods such as many plants and dairy products, but they are also added to processed and packaged foods.

Complex carbohydrates are made up of three different nutrients: starches, sugar, and dietary fibre. Fibre is not digested by the human body and is not counted in the total carbohydrate count. It is recommended that adults consume 30g of fibre per day.

Complex carbohydrates are good for the gut microbiome because they are a source of dietary fibre, which promotes healthy digestion and stabilises blood sugar levels. They can also lower blood cholesterol levels.

Complex carbohydrates include vegetables, nuts, and seeds. These foods also provide flavour and texture, which can enhance the eating experience.

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