5 Myths about Diabetes

Josephine Townsend (MNutr, RD).

We look at 5 common myths about Diabetes to help you know the truth about the disease.

Myth: Diabetes is reversible

I often see worrying headlines bandied about, such as this classic from a well-known sensationalistic tabloid newspaper “I reversed my diabetes in just 11 days – by going on a starvation diet” ! This statement is concerning for several reasons:

  • It may give false hope.
  • People may decide to put themselves on very restrictive diets without support from their healthcare team. This could result in nutrient
  • deficiencies and further health-related complications, in addition to potential harm if medication is not appropriately adjusted.
  • Not everyone will be appropriate or fit for extreme changes to diet, exercise or other. Certain co morbidities and possible risks should be assessed beforehand to establish safety.
  • Some people may develop unhealthy eating behaviours, such as eating disorders.
  • The ability to reverse diabetes may be confused between the different types, and we know that certain forms of diabetes cannot be reversed (e.g. type 1 diabetes).

However, it’s not all doom and gloom!

The positive news is that evidence does exist to show that Type 2 diabetes may be at least temporarily ‘reversed’ in some circumstances.. Normalisation of blood glucose levels has been observed in many people following bariatric surgery (1) , and success has also been seen with the use of “Very Low Calorie Diets’”(VLCD) to promote quick and significant weight loss. A VLCD tends to consist of meal replacement drinks, an extra allowance of non-starchy vegetables and plenty of sugar/calorie-free fluids to avoid dehydration.

However, the success of this diminishes with the duration of diabetes, and possibly with age and greater requirements for treatment too.

One study demonstrated that in a group of 29 people following an 800 calorie per day diet for 8 weeks and with an average weight loss of around 14 kg, 87% of those with a diagnosis of diabetes for less than 4 years were able to achieve ‘non-diabetic’ fasting blood glucose levels compared to 50% of those who had had diabetes for more than 8 years (2).

When breaking it down according to those who achieved a ‘non-diabetic’ HbA1c (see section on diabetes), an indication of longer term blood glucose control, 40% of those with diabetes for the shorter period managed this versus 14% of those who had had diabetes for longer. However, it is important to note there were limitations to this study, such as the small number of participants. This study was also controlled, whereas in real-life adherence to VLCD’s can be poor due to possible side effects including hunger, fatigue, dizziness, nausea , headaches, diarrhoea/constipation etc. It’s not the most sociable diet either!

There is a lack of evidence for the long-term effectiveness of VLCDs, and as we know it is also difficult for many to maintain weight loss once returning to normal eating, it is possible that diabetes will return with any weight regain or if pancreatic function deteriorates with age. It is not a miracle cure!

VLCD’s can be very helpful for some to aid weight loss and improve diabetes control, if not reverse it, but it is important that these diets are followed with the appropriate support, and are only short-term due to the risk of nutrient deficiencies. The positive effects are therefore only sustainable with the continuation of a healthy lifestyle – balanced diet, avoiding excessive food consumption and maximising physical activity.

Myth: Eating too much sugar causes diabetes

Please don’t punish yourself with the idea that you have given yourself diabetes due to eating lots of sugary things, as this simply isn’t the case!

It’s not the total amount of sugar we eat that causes diabetes (as confirmed by scientific studies).  However, if we do eat lots of sugary things which leads to excess energy (calorie) intake and weight gain, then we are more likely to develop type 2 diabetes (whereas weight is not linked to type 1 diabetes). This is because it’s the excess weight we carry that affects the body’s ability to regulate glucose levels in the blood.

However, a recent report by the Scientific Advisory Committee on Nutrition (3) did conclude that there is evidence to show an association between greater consumption of sugar-sweetened beverages and the incidence of type 2 diabetes.  So choosing diet sugar-free drinks is preferable.

Myth: Everyone with diabetes should eat a low carbohydrate diet

Media attention around this topic can certainly be overwhelming and confusing, but also very appealing when you hear all the promises of disappearing muffin tops or achieving a body not too dissimilar from a Victoria’s Secret model!

To keep it simple, there is insufficient evidence to suggest that a diet specifically low in the food group known as carbohydrate is beneficial for people with diabetes of any type (or for the general public without diabetes for that matter). It is for this reason that organisations including the British Dietetic Association and Diabetes UK do not actively advocate it.

Cutting down on carbohydrate intake can certainly aid weight loss in the short-term, which isn’t surprising when you think about how much carbohydrate foods contribute to our typical daily diets and therefore, how many fewer calories we are likely to consume! This would also mean a reduction in the extra butter we add to bread, cream added to pasta or cheese we top a jacket potato with, which again would significantly cut down on energy intake thus promoting weight loss. Of course this isn’t necessarily a bad thing if we are able to reduce our fat intake too.

But is this sustainable? And what about side effects, including fatigue, bad breath, constipation, headaches, etc? What about all the nutrients we’d be missing out on by removing certain carbohydrates from the diet  such as the fibre, vitamins and minerals found in whole grains, fruit, veg, pulses and some cereals?

There isn’t any evidence to show greater success from low carbohydrate diets than other dietary approaches in the long-term. Maybe portion sizes of carbohydrates have increased over the years and do need reducing, but this doesn’t need to be to the extent that would be classed as a low-carbohydrate or carbohydrate-free diet!


The SACN report highlighted evidence for the benefits of certain carbohydrate (3). This included an association between a greater intake of whole grains and/or dietary fibre and a reduced risk of high blood pressure, stroke and cardiovascular disease, and of course not forgetting the added benefits for bowel health including a reduced risk of bowel cancer. In fact, some research suggests that higher consumption of cereal fibre may actually reduce the incidence of type 2 diabetes mellitus!

An additional concern regarding a low carbohydrate/no carbohydrate diet would be a tendency to compensate with a greater intake of high fat/protein foods. This is likely to lead to an increase in saturated fat intake, which is linked to higher cholesterol – not good for heart health.

So whilst it may be beneficial for many to cut down on the quantity of carbohydrate piled on their plates, this does not have to mean a very low carbohydrate or carbohydrate-free diet. General guidelines are:

  • ~ 50% of our total daily energy intake should come from carbohydrates- including a minimum of 3 servings of whole grains and 5 portions of fruit and vegetables per day.
  • Aim to keep “free sugar” (sugar added to food products e.g. fizzy drinks, sweets, cakes, chocolate or the sugar/honey/syrup we add ourselves to drinks and cereal) to less than 5% of energy intake – ~ 7 tsp sugar per day (NB: a can of cola = 9 tsp of sugar!). 

However, if you do decide to pursue a low-carbohydrate diet, your healthcare team should work with you to ensure the safest possible outcome.

Myth: Foods marketed at people for diabetes are better for you

Anything labelled as diabetic, sugar-free or no added sugar is certainly tempting but it may not be all it’s cracked up to be.  Sugar-free can be better when it comes to versions of certain products, such as fizzy drinks, fruit squash or the odd mint. This is because they often are genuinely sugar-free and calorie-free (but it is always best to check the label to make sure).

However, if you decide to compare the labels of regular and diabetic marketed versions of chocolate, ice cream or biscuits it’s not unusual to discover that the latter contains the same amount, or if not more fat (and saturated fat) and therefore calories. This is because fat improves the flavour and other sensory qualities when sugar content is reduced (a key reason why we tend to gravitate towards fatty foods and we’ve seen the subsequent expansion of our waistlines over the years). These foods will also still be likely to contain a certain amount of sugar as they won’t have replaced it all, so please don’t assume they are sugar-free.

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Thinking something is suitable for diabetics may also lead us into a false sense of security so that we think it’s ok to eat more of it, even though it’s still high in fat and calories. We are all human after all!

If everything so far isn’t enough to put you off then another particularly unpleasant downside is the particular type of sweeteners commonly used in these products to add flavour; polyols (erythritol, xylitol, sorbitol, etc). When consumed in larger amounts these may trigger a laxative effect, which I’m sure for most people is an unwelcome side effect. In fact if you check the back of a packet of sugar-free chewing gum you may see the phrase “excessive consumption may produce laxative effects”, as it often contains the same sweeteners.

Of course the usual hefty price tag that accompanies these products is another off-putting factor and I rarely come across someone who has said they’ve tried and liked Diabetic products. The most sensible option is therefore to have a small of the good old tasty regular treats, as long as we know how to moderate ourselves and avoid overdoing it.

Myth: I can’t eat out as the food isn’t suitable for people who have diabetes

Please be reassured by the fact that there is NO such thing as a special diabetic diet! Life does not need to be miserable by cutting out all yummy foods or being the awkward friend at a party requiring a different menu.

In theory, the same healthy balanced diet is recommended for everyone, regardless of a diagnosis of diabetes. However, people with diabetes may need to be more careful around portion sizes of carbohydrate foods and/or adapting their treatment regimens according to what they’re eating and which medications they’re taking. And of course, if overweight it’s advisable to reduce energy intake. Despite this you can eat out at restaurants or have a piece of birthday cake on occasion! You can even scan the menu for healthier options or reduce a hefty portion size by taking half your meal home in a doggy bag if you want to be really virtuous. The only things that really ought to be cut out from the diet are sugar-sweetened drinks (e.g. fizzy drinks) and sweets, which cause quick spikes in blood glucose and are of no nutritional value.

However, there is nothing wrong with the odd treat here and there as long as the phrase ‘in moderation’ is understood and aims are being met, from good blood glucose control to managing weight and optimising cholesterol levels. But maybe a diagnosis of diabetes is a good reason to change up the regular routine when it comes to unhelpful eating habits and preparing meals – try new foods or get experimenting in the kitchen to create healthy but tasty meals for all the family and help prevent diabetes rearing its ugly head in each generation!


(1): Ardestani, A., Rhoads, D. and Tavakkoli, A. (2015) Insulin cessation and diabetes remission after bariatric surgery in adults with insulin-treated type 2 diabetes. Diabetes Care 38(4):659-664.

(2): Stephen, S. and Taylor, R. (2015) Restoring normoglycaemia by use of a very low calorie diet in long- and short-duration Type 2 diabetes. Diabetic medicine: a journal of the British Diabetic Association 32(9):1149-1155.

(3): SACN (2015) Carbohydrates and health. Norwich: TSO. Available at: https://www.gov.uk/government/uploads/system/uploads/attachment_data/file/445503/SACN_Carbohydrates_and_Health.pdf [ last accessed 21 March 2016].