Low carbohydrates diet: Defining it. Benefits for weight loss and other conditions. Pros and contras.

Many low carbohydrates diets or Ketogenic diets (LCD or KDs) have been created and studied, some of them very famous like: Dr. Atkins diet, South Beach diet, the Zone, Protein Power, etc. Many people question: Then, which is the best diet? And even more, are they safe?

Well, let me tell you, there is still no answer to that question. Even though, a lot of investigation has been made, there's still more to know and learn but, there are many things that point out that Low Carbohydrates Diets are better than High Carbohydrates or High fat Diets. We'll explain why soon.

Let's see what research documents say about a low carbohydrates diet, but before we begin, here's a little about the wonderful world of molecules (as a chemist, I simply love to know what happens inside the body because then I understand why in the physical world, things happen the way they do). Check this graphic, it will drive understanding of the whole subject.

The organism produces energy basically from 3 types of sources: Carbohydrates (basically Glucose), Proteins and Lipids or Fats.

When this molecules are broken into smaller ones, they go into your blood stream and are taken to the cells following different pathways. I will explain what happens when you eat foods rich in simple carbohydrates:

When your diet provides a high amount of simple carbohydrates (basically glucose), such molecule raises its levels in your blood stream and the pancreas releases high amounts of insulin too, this insulin is like a little cart that will transport this glucose to your cells in order to produce energy.

Though, here comes the "but"... If there's a huge amount of glucose (hyperglycemia) to be transported to the cells, and there's a big amount of insulin released (hyperinsulinemia), a series of processes will take place (many of them are inflammatory) and there's a possibility for one or more different risks.

Hyperglicemia and hyperinsulinemia are risks associated to:

* Obesity.

* Diabetes Type II or Diabetes mellitus.

* Cancer.

* Cardiovascular disease.

* Hypertension.

* Polycystic Ovary Syndrome, etc.

So, how do you know your diet is producing this phenomena? Check if you answer with "yes", because it could be happening to you. Let me ask you if any of the following happens in your body:

* Do you feel hungry even though you've just finished a meal?

* Do you feel the need of eating during the day when it isn't even time for that or when your hunger is "non-sense" at that point?

* Do you feel fatigued, dizzy, or have difficulty concentrating without a “give me something” snack between meals?

* Do you feel anxious after eating, especially after a meal rich in starches and sweets?

Let's go back to the graph. High glucose and high Insulin levels in your blood will make Insulin to block an enzyme called: Lipase and so, glucose will go and enter directly to your fat cells.

Inside the fat cells, glucose will enter to a metabolic pathway that will produce: Acetyl Coenzyme A and Alpha-Glicero-Phosphate. From Acetyl Coenzyme A, fatty acids will be formed, that combined with Alpha-Glycero-Phospate and the help of an enzyme will form Glycerol. If 3 molecules of this join with Fatty Acids, a Triglyceride results.

Triglycerides, are just one of many factors that are important markers of cardiovascular health. If this are high, as well as other markers like: Total cholesterol, High Low Density Lipoproteins ("bad cholesterol"), etc., the risk of a cardiovascular disease is high too.

What are Low Carbohydrates Diets?

First, from the name, you may deduct what this type of diet is about, but is easier to define them if I explain what Low Carbohydrates Diets or Ketogenic Diets are not:

+ This diets are not inflexible, they don't erase carbs from the list of nutrients to be taken.

+ By the way, they promote vegetables and fruits as sources of fine carbohydrates.

+ This are not only high protein diets. But they are low glycemic index.

+ This diets do not damage the kidneys, the heart, the liver or produce bone loss.

+ This aren't diets that necessarily have a low amount of fiber, because many low carbohydrate foods are high in fiber by the way.

The pros of low carbohydrate diets

After comparison of low-carbs diets and low fat diets (considering the same amount of calories), there are greater advantages in the former. The explanation departs on the issue that low fat diets seem to have lower metabolic efficiency.

With the first graph we saw that insulin and glucose are necessary for triglyceride formation, when few glucose is available, the body starts using fat as first source of energy, that's why low carbohydrate diets produce the following benefits:

1) They enhance body composition.

2) They help to reduce body fat.

3) The muscle mass increases (due to a process called ketosis on which the liver converts fat into fatty acids and ketone bodies which are used for energy. So the body keeps glucose for "emergencies" and doesn't use protein either.

The ketosis is not associated with metabolic acidosis (called ketoacidosis, a medical condition that causes dehydration, hyperglycemia, etc.) so it does not alter the kidneys, the liver or the heart.

4) These diets reduce appetite (because ketone bodies like beta-hydroxybutyrate are circulating and produce this effect).

5) A low carbohydrates diet induces metabolic activation of thermogenesis (this is a process that helps your body to produce heat and may help to lose weight because your metabolism is increased).

6) These diets increase the reduction of calories.

7) A low carbohydrates diet promotes a non atherogenic lipid profile (meaning that lipids do not accumulate to produce plaques in the arteries, a phenomena that may produce atherosclerosis and other conditions).

8) KDs can lower blood pressure, an advantage for people with hypertension.

9) These diets decrease the resistance to insulin.

10) KDs may have anti-inflammatory effect and may even be effective in reducing tumor size.

The utility of ketogenic diets

A Ketogenic or low carbohydrates diet is mainly used for:

1) Weight loss.

2) Cardiovascular Dysmetabolic Syndrome, characterized by:

+ Hypertension.

+ Dyslipidemia (high tryglicerides, high total cholesterol, high low density lipoproteins (low "good" cholesterol).

+ Glucose intolerance.

+ Hyperuricemia (high level of uric acid).

3) Carotid Intima-Medial Thickness (early indicator of atherosclerosis.

4) Type II Diabetes.

5) Epilepsy.

6) Cancer.

7) Polycystic Ovary Syndrome (a common female endocrine disorder characterized by obesity, irregular menstruation cycles, acne, excessive amounts of masculine hormones and abnormal blood lipid levels).

Some diets limit the amount of overall carbohydrate, while others focus on certain types of foods, generally ones high in starch and sugars, learn more about each type of Low Carbohydrates Diet. Get extra advice, recipes, etc. On this site

Are there any contras against ketogenic diets?

The body needs all types of molecules in order to function, so a low carbohydrates diet raises some controversies like:

+ Can ketogenic diets produce harm to the heart, the kidneys or the liver?

Defenders of these diets say that ketosis is not the same as acidosis.

They point that the body is capable to adapt to the change from a high carbs diet to a low carbohydrates diet in such way that brain cells that obtain almost all their energy from glucose can change to obtain 50-75% of the energy from fat, specifically from ketone bodies.

They comment that ketoacidosis appears fundamentally in pathological situations such as: diabetes mellitus and starvation (situations with lack or none insulin presence).

In low carbs diets, aminoacids and gastrointestinal hormones stimulate the release of few amounts of insulin, sufficient to avoid pathological situations that derive from its complete absence.

+ Can ketogenic diets imply limitations in physical activity?

The answer is no, but there is an exception. If the person performs activities that need anaerobic processes such as: weight lifting, sprints, abdominal workouts, the performance can be lower because these activities require glucose to produce energy. In the absence of oxygen, fatty acids may not be used to produce it.

Glucose metabolism and formation of ketone bodies

+ Some side effects have been reported in the treatment of intractable pediatric epilepsy.

Again, defenders say that diets for the treatment of this condition were usually high protein, high fat but very low in carbohydrates, producing not a mild ketosis as desired, but a high ketosis which then triggered effects such as:

- Hypoproteinemia.

- Lipemia.

- Hemolytic anemia.

- Fanconi's renal tubular acidosis.

- Marked increases in liver function tests.

+ When there's low levels of Selenium in the body, a low carbohydrates diet has been said to produce side effects like:

- Dehydration (47%).

- Gastrointestinal disturbances (38%) (nausea/vomiting, diarrhea and constipation).

- Others.

Most complications are transient and can be remedied with various treatments: Adequate supplementation and adjustments to the amount of nutrients.

+ Ketogenic diets may produce kidney stones?

A risk of high levels of uric acid (from a consumption of a high protein diet), and calcium formation, are the conjunction of hypercalciuria, acid urine and low urinary citrate excretion.

If there is a low intake of fluids during a low carbohydrates diet, the condition could appear. To avoid it, experts recommend about 3 liters of liquids/ day.

As a conclusion, this diets show many benefits though further research is needed on the safety and effectiveness of them, that's why it is so important to search for medical advice and supervision to see if a low carbs diet is a suitable option for you.

Diet is wrong understood. It doesn't mean starving, but enjoying. See some ideas for daily eating

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