Weight-loss & macronutrient diets
Low-carbohydrate diet
Reduces carbohydrate intake, though definitions and permitted amounts vary considerably, from under 130 g daily down to ketogenic levels.
What people typically eat
Meat, fish, eggs, dairy, nuts, non-starchy vegetables and some fruit; grains, potatoes and sugar are reduced.
What is restricted
Bread, pasta, rice, potatoes, sweets and sugary drinks, to varying degrees.
Why people try it
Weight loss and blood-glucose control; low-carb approaches are widely used in type 2 diabetes management.
Realistic advantages
- Often reduces hunger, protein and fat are satiating
- Can improve blood-glucose control and reduce medication needs in type 2 diabetes
- Short-term weight loss at least matches low-fat diets in trials
Realistic disadvantages
- Restrictive versions are hard to sustain and socially awkward
- Quality matters: a low-carb diet built on processed meat is not a healthy one
- Constipation and low fibre are common if vegetables are neglected
Strength of evidence
Moderate evidence
Good evidence for short-term weight loss and glycaemic improvement; long-term superiority over other calorie-matched diets is not established.
Likely cost and difficulty
Moderate cost; moderate difficulty.
Nutritional risks
Low fibre, raised LDL in some individuals, and nutrient gaps in strict versions.
Who should avoid it
People on insulin or sulfonylureas must not cut carbohydrate sharply without medication review, hypoglycaemia risk.
Is professional supervision advisable?
Advisable if you take glucose-lowering medication; medication often needs adjusting promptly.
References
Written by the Slimr editorial team. How we review diets.
