LCDs that prioritised high-quality protein, fat, and carbs from whole grains and plant-based foods were linked to lesser weight gain over time, the study said.
Published Dec 31, 2023 | 11:00 AM ⚊ Updated Dec 31, 2023 | 11:00 AM
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Following a low-carbohydrate diet (LCD) often aims to prompt swift initial weight loss by restricting carb intake, resulting in reduced water weight and overall calories. However, I think we can all agree that the expected outcomes are sometimes not achieved despite adhering to these diets.
A recent US-based study attempts to explain why this happens.
Recently, researchers from the Harvard TH Chan School of Public Health, and Brigham and Women’s Hospital in Boston, US, uncovered connections between the sources and quality of macronutrients in LCDs and their impact on long-term weight changes.
The study, published in JAMA Network, revealed that only LCDs that prioritised high-quality proteins, fats, and carbohydrates derived from whole grains and plant-based foods were linked to lesser weight gain over time. Conversely, diets emphasising animal-sourced proteins and fats or refined carbohydrates were associated with faster weight gain.
Low-carbohydrate diets (LCDs) have gained considerable attention, as they hold the promise of promoting weight loss and improving metabolic health. In clinical trials, LCDs, such as ketogenic diets with only 5-10 percent of energy from carbohydrates, have led to favourable short-term weight changes.
However, a few studies had considered the role of food group quality in the associations between LCDs and weight outcomes, the researchers said in their study.
“Our study goes beyond the simple question of ‘To carb or not to carb?’,” said lead author Binkai Liu in a statement. “It dissects the low-carbohydrate diet and provides a nuanced look at how the composition of these diets can affect health over years, not just weeks or months.”
However, a low-carb diet expert in India disagrees with the study. Shashikant Iyengar, a metabolic health coach and renowned low carb nutritionist, says that this study may not necessarily be applicable in the Indian context due to the difference in the type of food consumed by people of both countries.
“A high-quality LCD, rich in plant-based proteins, and healthy fats was associated with slower weight gain, while a lower-quality LCD was associated with the opposite result,” the study reported.
Speaking to South First, certified low carb diet coach Iyengar says, “The technical definition of a low-carbohydrate diet lies in the ideal range of 20 percent or less carbohydrate intake, which differs significantly from the classification used in the study, categorising it as 38.3 to 40 percent. While the study involves 1,23,000 participants, it doesn’t entirely align with the dietary practices many individuals in India follows.”
He adds that the classification of diets into plant-based and animal-based categories in the study presents complexities. For instance, while a beef burger is considered animal-based, a vegetarian burger would be categorised as plant-based.
“However, individuals consuming animal-based diets might include refined carbohydrates like buns made of maida, while those opting for plant-based diets typically consume more whole grains, legumes, and minimally-processed foods,” Iyenger explains.
According to him, the study’s comparison between diets doesn’t adequately account for these differences in carbohydrate sources and food preparation methods. For example, individuals consuming more whole foods, including salads, beans, and whole grains, might show less weight gain compared to those consuming more refined carbohydrates or deep-fried foods. This distinction in preparation methods seems to affect the observed weight outcomes.
Iyengar weighs in, “The study’s findings might not directly align with the Indian context due to differences in food choices and preparation methods. In India, our diet majorly consists of carbohydrates, with fat and protein intake being comparatively lower. However, we can modify our diets by reducing grains and increasing the consumption of pulses and legumes to enhance protein and fat intake. For instance, incorporating more eggs or nuts can be beneficial.”
He adds, “I’d like to mention the aspect of preparing animal-based foods healthily, such as grilling or baking fish instead of frying it, as these methods align with a low-carb, healthier diet.”
Even if one doesn’t strictly adhere to an extremely low-carb diet of 20 percent and instead maintains around 40 percent, making these dietary adjustments can still yield positive outcomes.
“While the study might not perfectly apply to our context due to dietary differences, it may suggest the superiority of plant-based foods, which might not be the case universally and could be a result of selective presentation,” Iyengar says.
In a low-carbohydrate diet, the focus is on reducing carbohydrate intake, which primarily includes grains, starchy root vegetables, sugars, and even fruits in our Indian diet — all of which fall under the category of starchy foods.
Iyengar explains, “Carbohydrate foods mainly comprise sugars and starches, prompting the need for their reduction. This fundamental understanding dictates that when carbohydrates are reduced, the intake of the other two macronutrients — fats and proteins — needs to increase or will naturally rise. Conversely, an increase in carbohydrate intake results in a decrease in either fats or proteins. Therefore, achieving balance becomes crucial.”
When reducing carbohydrates, the solution lies in automatically increasing the intake of protein-rich foods. These protein sources predominantly include non-vegetarian options. However, in the Indian vegetarian context, protein-rich foods encompass paneer (curd cheese) along with certain legumes and pulses like lentils, he adds.
Iyengar explains that maintaining a carbohydrate intake of around 20 percent can correspond to a balanced proportion of around 20 percent protein and approximately 60 percent fat in a diet. When incorporating fats, it’s crucial to focus on the sources coming naturally with certain foods like paneer, curd, and cheese.
For instance, when consuming chicken, the natural fats present in the meat, especially with the skin, and minimal additional fats, such as ghee or butter, are used for cooking purposes.
Reducing carbohydrate intake prompts an increase in protein consumption, which can be sourced from eggs, pulses, lentils, and legumes for vegetarians. Even if the carb intake stays around 40 percent, it can still yield beneficial results, Iyengar concludes.
