Going low carb, is it advisable?

Going “low carb” has become fashionable in recent years. “Low carb” is short for low carbohydrates in the diet. The standard dietary recommendation states that adults should get 45%-65% of their energy from carbohydrates, 20%-35% from fat, and 10%-35% from protein [1]. By reducing the energy intake from carbohydrates, their diet will include a much higher percentage of fat and protein sources compared to normal. By doing so, they avoid all food rich in carbohydrates such as rice, noodles, bread, sugar, root vegetables, and even sweet fruits. People who follow very-low-carbohydrate diets, such as the ketogenic diet, may intentionally reduce the intake carbohydrates to as low as only 5%-10% [2].

Carbohydrate-rich food.

The rationale of going for low carbohydrates is to force the body to make use of fat and protein as alternative fuels to glucose. Proponents of the low-carbohydrate diet claim that the diet is effective in losing weight. It can also help to improve insulin control, to lower cholesterol, and thus reducing the risk of many chronic conditions such as diabetes and cardiovascular diseases. Indeed, these claims are supported by scientific studies [2]. Many randomised-control clinical trials found ketogenetic diets to be better than low-fat diets in weight loss. Ketogenic diets can help patients lose about 2 kg more than low-fat diets do at 1 year [3]. Hence, no doubt, going “low carb” is one effective way to induce short-term (< 2 years) weight loss.

A healthy ketogenic diet can be an effective way to lose weight in the short-term.

The question remains whether one can continue “low carb” for the long term? It was found that the short-term benefits of weight loss may be outweighed by longer-term cardiovascular harms [4]. A long-term study that followed 43,396 Swedish women for an average of 15.7 years found that by lowering carbohydrates and increasing proteins in the diet, the risk of cardiovascular disease increases [5].  Another research which reviewed the results from 17 studies also found that low-carbohydrate diets were associated with a significantly higher risk of all-cause mortality [6]. Therefore, following going “low carb” for more than a couple of years may be risky! This is because, by restricting the intake of carbohydrates, one usually eats more animal-based proteins, especially red meat and saturated fat. Even well-qualified dieticians find in challenging to keep a low-carbohydrate high-fat diet within the recommended >10% saturated fat intake threshold with animal proteins [7].

Don’t keep to a low-carbohydrate diet for too long. Add whole grains to your diet once you have achieved your targeted weight.

To conclude, going “low carb” is a feasible and practical approach to induce weight-loss. However, one should not keep a low-carbohydrate diet for more than 1-2 years to avoid any long-term irreversible harm. To maintain good health, one should follow healthy dietary guidelines by taking more vegetables, plant-based proteins, and reduce the intake of animal-based saturated fat.

Eat more vegetables and plant-based proteins even if you want to go “low carb”.


[1]        Dietary Reference Intakes for Energy, Carbohydrate, Fiber, Fat, Fatty Acids, Cholesterol, Protein, and Amino Acids : Health and Medicine Division, (n.d.). http://www.nationalacademies.org/hmd/Reports/2002/Dietary-Reference-Intakes-for-Energy-Carbohydrate-Fiber-Fat-Fatty-Acids-Cholesterol-Protein-and-Amino-Acids.aspx (accessed August 20, 2019).

[2]        W. Masood, K.R. Uppaluri, Ketogenic Diet, StatPearls Publishing, 2019. http://www.ncbi.nlm.nih.gov/pubmed/29763005 (accessed August 20, 2019).

[3]        R. Ting, N. Dugré, G.M. Allan, A.J. Lindblad, Ketogenic diet for weight loss, Can. Fam. Physician. 64 (2018) 906. https://www.ncbi.nlm.nih.gov/pubmed/30541806.

[4]        A. Floegel, T. Pischon, Low carbohydrate-high protein diets., BMJ. 344 (2012) e3801–e3801. doi:10.1136/bmj.e3801.

[5]        P. Lagiou, S. Sandin, M. Lof, D. Trichopoulos, H.-O. Adami, E. Weiderpass, Low carbohydrate-high protein diet and incidence of cardiovascular diseases in Swedish women: prospective cohort study, BMJ  Br. Med. J. 344 (2012) e4026. doi:10.1136/bmj.e4026.

[6]        H. Noto, A. Goto, T. Tsujimoto, M. Noda, Low-carbohydrate diets and all-cause mortality: a systematic review and meta-analysis of observational studies., PLoS One. 8 (2013) e55030–e55030. doi:10.1371/journal.pone.0055030.

[7]        C. Zinn, A. Rush, R. Johnson, Assessing the nutrient intake of a low-carbohydrate, high-fat (LCHF) diet: a hypothetical case study design, BMJ Open. 8 (2018) e018846. doi:10.1136/bmjopen-2017-018846.

2 thoughts on “Going low carb, is it advisable?

  1. Lisa McLean Reply

    Good summary of the evidence Soo Liang and excellent conclusion. I love your newsletters.

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