We had the pleasure of interviewing the 2020 Australian of the Year Dr James Muecke, on Osana’s Prevention Hacks podcast. James has had a distinguished career as an eye surgeon helping countless individuals around the world see, and now he is highlighting the dangers of sugar and refined carbohydrates in our diet, as a precursor to a host of chronic illnesses, not just diabetes.

Let’s examine the evidence for sugar as a factor towards good or bad health:

  • Most of us know that sugar can increase the risk of diabetes and being overweight. This is mostly due to excess calories, or eating more than you need. However recent research shows that sugars can directly harm the liver and cause insulin resistance, where insulin is less effective in processing sugar in the body, leading to type 2 diabetes. Interestingly, artificial sweeteners can also cause insulin resistance and cardiovascular disease. Reducing refined carbohydrates in established diabetes can drastically reduce weight, improve sugar control and even reverse diabetes, according to a study published in the British Medical Journal
  • Sugar can cause cognitive decline and lead to Alzheimer’s disease, which many are now calling type 3 diabetes. A large study of over 5,000 participants followed up over 10 years showed faster cognitive decline in those with high sugar or refined carbohydrate diets (80% higher risk of dementia with these diets). Hypotheses that are currently being tested include protein accumulation in the brain (Amyloid), weak blood vessels leading to mini-strokes, or due to high insulin levels itself (high risk of dementia can occur with well-controlled diabetes patients on insulin)
  • Sugar and refined carbohydrates, such as processed biscuits, white bread, pasta and rice, can lead to heart disease, more so than saturated fat
  • It can lead to mood swings, anxiety and depression. Sharp elevations in mood followed by a trough, which occurs when sugar is metabolised, can provoke a stress response, which is evidenced by high cortisol levels in the body. Eating sugary food makes us feel good due to the “sugar high”, but this can be a vicious cycle
  • Sugar, especially fructose is linked with attention deficit disorders, aggression, impulsive behaviour and bipolar disorder.
  • Sugar can cause inflammation, and precipitate asthma, allergies and hayfever. Kids drinking sugary fruit drinks more than 5 times per week show 2.5 times greater allergy sensitisation than those drinking only 1-3 per week
  • It can cause headaches and disrupt sleep. Headaches arise from high or low sugar levels (you get more fluctuations from eating sugary foods) as well as from associated dehydration. Sugar uses up magnesium which helps you relax, causes cravings and sugar highs make it hard to get restful sleep. Avoid sugar, and food in general, 3 hours before you go to bed.

The Health Minister is commissioning a review of Australia’s dietary guidelines and we are encouraging everyone to reconsider their sugar and refined carbohydrate intake. As per our other blog articles, we recommend a greater portion of plants (up to 8 servings per day), and a more Mediterranean diet of fish, legumes, seeds, nuts, fruits, whole grains and olive oil. We are launching Osana’s new podcast and you can tune in on a regular basis through our website and Facebook page.


  • https://www.medicalnewstoday.com/articles/317246
  • https://www.healthline.com/nutrition/does-sugar-cause-diabetes#bottom-line
  • https://www.theatlantic.com/health/archive/2018/01/the-startling-link-between-sugar-and-alzheimers/551528/
  • https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5793267/
  • https://www.sciencedaily.com/releases/2016/01/160113103318.htm
  • https://www.healthline.com/health/depression/sugar-and-depression
  • https://www.webmd.com/asthma/news/20080317/sugar-intake-linked-to-kids-asthma#:~:text=Kierstein%20and%20colleagues%20hypothesized%20that,wheezing%20and%20shortness%20of%20breath
  • https://thatsugarmovement.com/sugar-and-allergies-in-kids/
  • https://www.insider.com/can-sugar-cause-headaches
  • https://nutrition.bmj.com/content/early/2020/11/02/bmjnph-2020-000072
  • https://www.news.com.au/lifestyle/food/drink/diet-drinks-may-be-just-as-bad-for-your-health-as-fullsugar-versions/news-story/007d57d713a9d86e014ad7f067ce9f09
  • https://www.miragenews.com/high-fructose-intake-may-drive-aggressive-behaviors-adhd-bipolar-disorder/