CHENNAI: Carbohydrate cutting, or reducing the intake of carbohydrates in one’s diet, is a popular strategy for weight loss and improving metabolic health. This approach typically involves limiting foods like bread, pasta, rice, and sugary snacks, while increasing consumption of proteins and fats. Carbohydrates are the body’s primary energy source, and by cutting them, body is forced to burn fat for fuel, a process known as ketosis.
This shift can result in significant weight loss and improvements in insulin sensitivity. However, carbohydrate reduction can also have side effects, such as fatigue, brain fog, and muscle cramps, especially in the initial stages as the body adapts.
Today, there continues to be interest in low-carb approaches. Food contains three macronutrients: carbohydrates (4 kcal/g), fat (9 kcal/g), and protein (4 kcal/g). Low-carbohydrate (low-carb) diets have been a strategy for weight loss, and they can be classified as follows:
Very low-carbohydrate (<10% carbohydrates) or 20 to 50 g/d
Low-carbohydrate (<26% carbohydrates) or less than 130 g/d
Moderate-carbohydrate (26%-44%)
High-carbohydrate (45% or greater)
Before the discovery of insulin, the removal of high-glycaemic carbohydrates such as sugar and flour from the diets of diabetics was found to be a successful method of controlling glycosuria (sugars in urine). An analysis of the pattern of food consumption during the more recent obesity and diabetes epidemic found that the increase in calories was almost entirely due to an increase in carbohydrates. Given this context, it is reasonable to postulate that diets low in carbohydrates may be as healthy as, or even healthier than, the higher-carbohydrate diets introduced into modern society only recently.
When reducing carbohydrates from the diet, the macronutrient intake of fat and protein generally increases to compensate for the reduction of carbohydrates.
Ketogenic diets
Keto diets restrict carbohydrates to induce nutritional ketosis and limit carbs to 20 to 50 grams daily. Restricting carbs to under 50 grams induces glycogen depletion and ketone production by mobilising fat stored in adipose tissue.
A low-carb diet may have beneficial effects in terms of weight loss, type 2 diabetes and cardiovascular risk factors. They do have positive effects on body weight, BMI, abdominal circumference, blood pressure, high-density lipoprotein cholesterol (HDL-C), triglycerides, glycemia, haemoglobin A1c (HbA1c), insulin, and C-reactive protein (CRP).
However, following a low carbohydrate for too long can have adverse effects on the body.
(i) Dyslipidemia: A ketogenic or low-carb diet does increase good cholesterol (HDL) and reduces triglyceride levels in the blood. However, increases are observed with the bad cholesterol (LDL) as well as the total cholesterol levels which may promote atherosclerotic properties (build-up of fat in the artery walls)
(ii) Nutritional Deficiencies: Due to the lack of diversity in terms of plant and fibre-based food (unless the diet is well-balanced), there are chances of nutrient deficiencies. Eg: Vitamin C due to the lack of fruits as they are commonly restricted in a low-carb diet.
(iii) Sustainability: Strict carb-cutting diets can be hard to maintain long-term, leading to potential weight regain or unhealthy eating patterns.
(iv) Sports Performance: While low-carb diets may be an effective option for athletes who aim to lose body weight (BW) and body fat while sparing muscle mass, however, negative implications like reduced glycogen levels, slower recovery, and mental fatigue do exist.
Unfortunately, there are substantial limitations as above to the Low Carb Diet that restrict its metabolic efficacy over the longer term, coupled with potential safety concerns. Compared with the low-carb diet, caloric restriction offers a greater selection of food options with fewer safety concerns (provided maintenance of a balanced diet). Perhaps, even a relatively modest caloric restriction provides a practical, feasible and enjoyable dietary alternative to the Low Carb Diet, accomplishable over the longer term and offering hope for the future.