Does eating a lot of sugar give you type 2 diabetes?
Sugary drinks clearly and demonstrably increase your risk of type 2 diabetes. Sugar from solid food barely does. The biggest difference comes from drinking fewer sugary drinks, exercising more and losing weight.
Sugary drinks are the clearest culprit. People who drink one to two glasses of soft drinks, energy drinks or fruit drinks per day have a 25 to 26 percent higher chance of developing type 2 diabetes. This is shown by a meta-analysis of eight large population studies involving more than 310,000 participants. Even fruit juice counts: each additional serving per day is associated with a five percent higher risk. The association has been found in multiple independent studies and is statistically robust.
Sugar from solid food works differently. Eating more sugar through regular food is not associated with a higher rate of diabetes. For added sugar consumed through food, no association was found at all. At 20 grams of extra sugar per day through food, the risk was slightly lower. The quality of evidence is low to moderate, but the message is consistent: the form in which sugar is consumed matters. Liquid sugar appears to be more harmful, presumably because drinks make you feel full more slowly and the sugar reaches your bloodstream more quickly.
Early-life exposure may also play a role. Historical research into British sugar rationing after the Second World War shows that people who consumed little sugar during pregnancy and infancy had approximately 35 percent lower odds of developing type 2 diabetes later in life, and developed the disease an average of four years later. It is not a classic randomised study, but the finding points to a possible causal relationship early in life.
Being overweight and getting too little exercise are the most strongly proven, reversible risk factors. In a randomised study with 3,234 participants at elevated risk, a lifestyle programme aimed at seven percent weight loss and 150 minutes of exercise per week reduced the risk by 58 percent. That is stronger than medication: the diabetes drug metformin reduced the risk by 31 percent in the same study.
Besides sugary drinks, processed meats and red meat are the food groups with the strongest evidence for an increased risk. According to one large meta-analysis, people who consume large amounts of these products in combination can even triple their risk. So pay attention to your drinks, processed meats and body weight at the same time if you want to lower your risk.
The findings are based on two large meta-analyses (one of which included more than 310,000 participants), one randomised study (the Diabetes Prevention Program, n=3,234), and one historical quasi-experiment (British sugar rationing). Most of the evidence linking sugar to diabetes is associational, meaning it was found in population studies, and has not been established as causal through randomised studies.
Is intermittent fasting safe if you have type 2 diabetes?
Intermittent fasting can be safe in type 2 diabetes, but only if you do this in consultation with your doctor, because your medication will almost always need to be adjusted to prevent blood sugar from dropping too low.
What is the relationship between fatty liver and type 2 diabetes?
Fatty liver and type 2 diabetes mutually reinforce each other: they share the same underlying mechanism and roughly double each other's risk. If you have a fatty liver, addressing it is also a way to reduce your risk of diabetes.
How do I know if my blood sugar is healthy (prediabetes)?
Prediabetes can be measured reliably, but no single blood test provides complete certainty on its own. If in doubt, have multiple values measured and discuss with your doctor whether a lifestyle programme or medication is worthwhile, because that difference has been proven to matter.
Does eating more fibre help against high blood sugar?
Eating more water-soluble fibre probably helps in lowering high blood sugar, but the overall meal composition also plays a role. Choose legumes, vegetables and fruit if you want to increase your fibre intake, and watch out for side effects when making a large increase.
Does having type 2 diabetes increase your risk of certain cancers?
Type 2 diabetes increases the risk of several cancers, including liver, pancreatic, uterine and colorectal cancer. If you have diabetes, it is worthwhile to discuss with your doctor whether closer attention to early detection or lifestyle improvement is appropriate for you.
Does type 2 diabetes increase your risk of dementia?
Type 2 diabetes substantially increases the risk of dementia, and the younger you are at diagnosis, the greater that risk. Good blood sugar management and the choice of medication appear to be relevant; discuss this with your doctor if you have diabetes.