Low carbohydrate (low-carb) diets have become increasingly popular, as they can be effective in reducing the risk for and reversing chronic conditions like type 2 diabetes, balancing hormones, and losing excess weight (1).
Low-carb diets have strategically been used for weight loss since the 1800s (2).
What is a low-carb diet?
Although there is no clear definition for a low-carb diet, the carbohydrate content can be generally defined this way (2):
· Very low-carb = <10% carbs or 20-59 grams/day
· Low-carb = <26% carbs or less than 130 grams/day
· Moderate-carbs = 26%-44% carbs
· High-carb = 45% or greater carbs
For example, a diet that contains about 200 grams of carbohydrates can be classified as a moderate-carbohydrate diet when the total calorie intake is 2000 calories/day (3).
How many daily calories support weight loss?
The number of calories (energy) that a person requires each day will vary depending on factors like age, height, weight, activity level, and metabolic health status.
However, a general rule of thumb for weight loss is to take in 500 fewer calories each day from the level that your body needs to maintain your current weight, which can help you safely lose about 1 pound of body weight each week (5).
Women need, on average, about 2000 calories/day to maintain weight, while men require about 2600 calories/day to maintain weight.
Women with weight loss plans can consume about 1500 calories/day, while men with weight loss plans require about 2100 calories/day to lose about 1 pound of body weight each week.
Low-carb meal plan example
A low-carb meal plan based on 1500 calories/day for weight loss, may look like this for one day (4):
Breakfast: 2 eggs (154 calories/0 carbs), 1 small apple (52 calories/13.8 g carbs), 1 tbsp. almond butter (98 caloires/3 g carbs), ½ tsp. cinnamon, ground (3 calories/1 g carbs)
Lunch: Tuna salad: 5 ounces tuna (175 calories/0 carbs); 1 small celery stalk (2.7 calories/1 g carbs); ½ tbsp. mayonnaise (50 calories/0 carbs); 1 tsp. mustard (0 calories/0 carbs); 5 grape tomatoes (7 calories/2.74 g carbs); 1 tbsp. chopped red onion (5.6 calories/1.3 g carbs); 1 tsp. dried parsley (1.4 calories/.3 g carbs). Avocado (227 calories/11.8 g carbs), 1 large brown and wild rice cake (70 calories/16 g carbs), 1 ounce Manchego cheese (130 calories/0 carbs), ½ cup blueberries (60 calories/15 g carbs).
Dinner: 1 cup diced or about 4-5 ounces chicken thighs (293 caloires/0 carbs), 1 cup brown basmati rice (160 calories/34 g carbs), 1 cup roasted broccoli (30 calories/6 g carbs). Day totals: Calories = 1518.70, Carbs = 105.94 g
A low-carb diet generally focuses on proteins, healthy fats, and some non-starchy vegetables. In general, those consuming a low-carb diet will eat meat (beef, chicken), fish (salmon, trout, haddock), eggs, healthy oils/fats (coconut, olive, and butter), high-fat dairy, vegetables like broccoli and carrots, some nuts and seeds, and perhaps a little fruit like lemons, blueberries, and cherries.
Further benefits of a low-carb diet
In addition to weight loss, a low-carb diet has been found to improve cardiovascular disease markers like inflammation and endothelial dysfunction, which are the initial markers in the development of this leading cause of death and disability in the United States (6). Lowering carbohydrate intake is also associated with improvements to glycemic control in those struggling with diabetes as it was found to lower A1c levels and enabled the patient to reduce their anti-diabetic medication dosage (3).
Concerns about the low-carb diet
Although a low-carb diet can be beneficial when working to achieve optimal body weight and improve health status, it may not be appropriate for the long term. For example, restriction of carbohydrates can also reduce the intake of certain important nutrients, like potassium, which can lead to nutrient deficiencies over time (3). Further, reducing carbohydrate intake may be harmful to beneficial gut microbes, which can also lead to dysfunction over time (3). Being aware of essential nutrient intake and levels is important when making dietary changes over longer periods, and working with a health care professional skilled in nutrition is advisable to help you safely accomplish your weight and health goals.