Sugar Avoidance

Our rating
 Question mark: This treatment has not been properly researched. It is not possible to say whether they are useful or not.


The rating system

  • 3 smiliesThese treatments are very useful. They are strongly supported as effective by scientific evidence.
  • 2 smiliesThese treatments are useful. They are supported by scientific evidence as effective, but the evidence is not as strong.
  • 1 smileyThese treatments are promising and may be useful. They have some evidence to support them, but more evidence is needed to be sure they work.
  • No smiley On the available evidence, these treatments do not seem to be effective.
  • Question markThese treatments have not been properly researched. It is not possible to say whether they are useful or not.
  • Exclamation MarkSafety or other concerns have been raised for the use of these treatments.

What is it?

Sugar comes in many forms and is found in a wide variety of foods. Sugars may be naturally occurring (e.g. the sugar found in fruits) or refined and added to foods (e.g. sugar in soft drinks or the sugar you add to a cake when baking). Cutting out refined sugar from the diet has been proposed to improve mood in some cases, and recently there has been a rise in the popularity of sugar free diets.

How does it work?

There is evidence that eating foods rich in carbohydrates (sugar is a simple carbohydrate) produces a temporary improvement in mood. However, it has been proposed that eating (or drinking) excess amounts of sugar may cause changes in the body which can lead to lead to depression and overall reduction in wellbeing. In these cases, it is suggested that cutting out refined sugar may improve mood.

Is it effective?

In general, large studies have found that having a healthy diet (eating lots of fresh fruit and vegetables, lean proteins and wholegrains) is associated with a lower risk of depression. There is also good evidence from studies of large numbers of people that having a diet which is high in added sugar is associated with having depression symptoms. These studies show that having a lower intake of sugar may be associated with less risk of developing depression.

However, there have been no good quality scientific studies that have looked at the effectiveness of adopting a sugar free or low sugar diet as a way to treat depression.

Are there any disadvantages?

There are no known disadvantages.

Where do you get it?

If you would like to know more about the role of sugar in your diet, you can seek the help of a dietitian who can assess whether you have any sensitivity to sugar and advise you on any changes to your diet.


Given the lack of evidence on sugar avoidance, it cannot be recommended as a treatment for depression.

Key references

  • Kaiser A, Schaefer SM, Behrendt I, Eichner G, Fasshauer M. Association of sugar intake from different sources with incident depression in the prospective cohort of UK Biobank participants. European Journal of Nutrition. 2023; 62(2):727-38.
  • Li Y, Lv M-R, Wei Y-J, Sun L, Zhang J-X, Zhang H-G, et al. Dietary patterns and depression risk: A meta-analysis. Psychiatry Research. 2017; 253:373-82.
  • Park SK, Chung Y, Chang Y, Oh C-M, Ryoo J-H, Jung JY. Longitudinal analysis for the risk of depression according to the consumption of sugar-sweetened carbonated beverage in non-diabetic and diabetic population. Scientific Reports. 2023; 13(1):12901-.
  • Reis DJ, Ilardi SS, Namekata MS, Wing EK, Fowler CH. The depressogenic potential of added dietary sugars. Med Hypotheses. 2019; 134:109421.
  • Wang Y, Zhao R, Wang B, Zhao C, Zhu B, Tian X. The Dose-Response Associations of Sugar-Sweetened Beverage Intake with the Risk of Stroke, Depression, Cancer, and Cause-Specific Mortality: A Systematic Review and Meta-Analysis of Prospective Studies. Nutrients. 2022; 14(4):777.

Last reviewed and updated: 27 November 2023