Are low-carb diets driving malnutrition levels – can F&B help?

Since its popularisation by Dr Atkins​ in the early 1970s, the low-carb diet, or Atkins diet, has been regarded as a fast and easy route to weight loss. And more recently, it’s being used as a way to help manage prediabetes, type 2 diabetes, and other metabolic health conditions.

But critics claim this approach to eating and drinking is too simplistic and can lead to malnutrition if it’s not properly managed.

“Because it’s so restrictive, a low-carb diet can be challenging for some people to follow in the long term,” says Christina Vetter, health and food expert for gut-health brand, Zoe. “To get all the nutrients you need, it’s important to have a healthy, varied diet full of high-quality foods. Because low-carb diets restrict your intake of many foods, you could miss out on vital nutrients.”

Now, a study from the University of Vermont, looks at both sides of the argument, to better understand the health implications of a diet low in carbohydrates. And we look at what this means for the food and beverage industry.

Is the low carb diet damaging to overall health?​

The simplicity and speed of the low-carb diet’s effect on weight has led to it becoming one of the most widely adopted diets in the western world, with the global market valued at 12.49 billion USD in 2023, according to market insight firm, Data Bridge. 

The study, conducted by researchers Lani Banner, Dr Beth H Rice Bradley and Dr Jonathan Clinthorne, assessed the nutrient adequacy of three different low-carb meal plans.

1. The first plan contained an average of 20 grams of net carbs per day
2. The second contained an average of 40 grams of net carbs per day
3. And the third contained an average of 100 grams of net carbs per day

All three plans met the consensus definition of a low-carb diet, which includes less than 130 grams of carbohydrates per day.

The team found that all three low-carb meal plans safely exceeded the nutrient needs for vitamins A, C, D, E, K, thiamin, riboflavin, niacin, folate, and vitamins B6 and B12, for both men and women aged 31-70.

“Our findings suggest that, in addition to their well-established ability to support weight management, low-carb eating patterns can actually help promote better diet quality and close critical nutrient gaps,” says study co-author Dr Beth Bradley, researcher in the Department of Nutrition and Food Sciences at the University of Vermont.

The team did note that the meal plans did fall short of some nutrients for certain sub-populations with higher needs. These include iron for younger women and calcium for older adults.

Notably, the two meal plans, containing 40 grams and 100 grams of net carbohydrates, also provided more than the daily recommended intake of fibre.

“The idea that a low-carb diet must also be low in fibre is simply not supported by the data,” explains Dr Bradley. “High-fibre foods are actually an important part of a low-carb lifestyle, in part because fibre-rich food choices can help lower net carbohydrate intake. Non-starchy vegetables, nuts, and seeds, and, in moderation, even higher-carb fruits, starchy vegetables, and whole grains can contribute fibre to the diet while keeping overall net carb intake in check, especially in the more liberal low-carb approach.”

And while all three of the low-carb meal plans were higher than the recommended dietary allowance (RDA) for protein, the researchers highlighted that these protein levels still fell within the Acceptable Macronutrient Distribution Range of 10-35% of daily calories. Therefore, the meal plans provided more protein than needed to prevent deficiency but not deliver an excessive amount that would be considered unsafe.

“Nutrition is often more complex than simply tallying the totals you see on a menu or a food label,” says Dr Bradley. “Which foods your nutrients come from and how they fit within the broader context of your overall diet may play a more important role in determining health outcomes.”

How can food and beverage capitalise on popularity of the low-carb diet?​

Food and beverage manufacturers can capitalise on the low-carb diet by producing meals that provide all of the necessary nutrients that individuals need. If consumers are concerned that poor management of the low-carb diet could lead to malnutrition then offering complete meal options, through ready meals or meal-replacement drinks​ could be a huge benefit to consumers and a new opportunity for the industry.

“Manufacturers should look to develop products to help consumers follow this challenging diet,” says Stephanie Mattucci, associate director of food science for market insight firm, Mintel.

Source: Nutrient analysis of three low-carbohydrate diets differing in carbohydrate content
Published online: 30 August 2024
DOI: 10.3389/fnut.2024.1449109
Authors: Lani Banner, Beth H Rice Bradley, Jonathan Clinthorne