The last decade has seen a surge in diabetes prevalence from 1.4 million to 3.5 million cases in the UK alone[1]. As a result, diabetes ranks fifth highest among the most common causes of death worldwide, accounting for one to two million deaths each year[2]. Experts suggest another 10 to 20% rise in diabetes prevalence in the next decade, but why is this happening?
While the modern food environment is a leading factor, the incomprehensible minefield of conflicting information can make it hard to avoid becoming another diabetes statistic. Even doctors and medical professionals give non-evidence-based advice[3].
Your lifestyle habits play a critical role in your diabetes risk, so poor advice can often do more harm than good. Read on for a clear insight into how lifestyle impacts type 2 diabetes so that you can make informed decisions to manage your health.
1. Weight loss reverses fatty liver
Experts theorise that diabetes stems from gaining more fat than a person’s body can ‘manage’. In 2013, researcher Roy Taylor brought forward his ‘twin cycles’ hypothesis to explain this phenomenon[4]. He showed that when people gain fat above a certain level (known as their ‘personal fat threshold’), it increases visceral fat around their liver and pancreas. This visceral fat accumulation is critical because as this happens, these organs become insulin resistant.
Insulin resistance is where your cells don’t respond to insulin appropriately to store nutrients, and your body pumps out more to compensate. Under normal circumstances, insulin communicates with the liver to stop producing unwanted glucose. However, excess visceral fat interferes with this messaging, meaning that the liver continues to pump out glucose, resulting in dangerously elevated blood sugar levels. At the same time, fat leaks into the pancreas, damaging the insulin-producing beta-cells, meaning that your body can no longer prevent blood sugars from continuously rising. Over time, this accumulates and leads to severe diabetes outcomes like heart disease, blindness, or even limb amputation.
Fortunately, research shows that significant weight loss can reduce visceral fat levels to reverse type 2 diabetes. A landmark paper, the COUNTERPOINT study, shows us how potent fat loss can be for diabetics[5]. After eight weeks on a weight loss diet, participants lost 15kg on average. They also reduced their insulin levels and blood sugars down to normal, all directly correlated with changes in visceral fat. Their HbA1c readings, which measure advanced glycated end products (AGE) in the blood, decreased to normal levels. A follow-up study demonstrated that weight loss maintenance also results in long-term reversal of diabetes, as patients who maintained their weight loss no longer required medical treatment for the condition[6].
2. The best diet is the one that helps you lose weight
Nutrition can be a minefield for diabetics, with conflicting information on which foods they ‘should’ and ‘shouldn’t’ eat. Specifically, many ‘experts’ put a considerable emphasis on lowering carbohydrate intake, as this macronutrient spikes insulin and blood sugars more than any other[15].
While carbohydrates play a role in diabetes, nearly all research shows that weight loss, and specifically fat loss, is the most significant contributor to reversing type 2 diabetes, which you can achieve using various strategies.
Research consistently shows that you can lower your blood sugars and insulin levels with weight loss and that differences in food choices, macronutrient ratios, and meal timing are negligible[16],[17],[18]. If you’re concerned about your risk for diabetes, focus first on total calorie intake and food quality.
3. Exercise improves diabetes via enhanced glucose uptake and storage
Exercise is possibly the single most impactful lifestyle tool for improving your health, so it’s no surprise that regular physical activity and resistance training form a cornerstone of diabetes management. In general, research consistently shows that people who do more exercise and physical activity are less likely to be diabetic[7],[8].
While physical training can help manage diabetes through weight loss, there’s much more to exercise than just the calorie burn. In a nutshell, exercise transforms your muscles into glucose sponges, allowing them to soak up the sugars in your blood more efficiently for up to 48 hours after your session[9]. This process is known as insulin-independent glucose uptake and is one of the reasons experts recommend that diabetics take a walk after their meals[10].
Another benefit of long-term exercise is that it can enlarge your body’s glucose stores[11]. Most people can store around 500g of glycogen (the stored form of glucose) intramuscularly, but if you increase your muscle surface area, you also improve your ability to stockpile glucose[12]. This provides additional capacity to store excess sugars, preventing them from accumulating in your blood. Strength training also chronically increases your ability to store and uptake glucose over time[13].
While all forms of exercise improve glucose metabolism, resistance training is particularly potent, as it is far and away the most effective way to build and maintain muscle mass and improve body composition[14].
4. Sleep is a critical component of diabetes management
Sleep is possibly the most overlooked health-enhancing tool for people with diabetes. One 2012 paper showed that if you sleep five hours or less per night, your risk for diabetes doubles compared to someone sleeping seven or more hours per night[19].
Sleep loss is a form of stress that is closely linked to diabetes, and research demonstrates that it strongly influences the stress hormone cortisol[20]. When you perceive something as stressful, your body releases the hormones cortisol and adrenaline, so you can respond and adapt to our ever-changing environment. While the body can adapt relatively well to acute (short-term) stressors, it can result in chronically elevated cortisol when these become chronic (long-term).
Certain sleep stages (short-wave sleep) inhibit cortisol production and allow your body to rest and recuperate[21]. In essence, when you lose sleep, your body can’t lower cortisol levels, and you remain in a stressed state.
Another mechanism linking cortisol to diabetes is how cortisol tells your body to make glucose available to fuel your working muscles and organs. This process is essential if the context is correct, for example, preparing for a heavy lift in the gym. During chronic stress, cortisol unnecessarily increases glucose production and glycogen breakdown. As a result, persistent short sleep leads to higher blood sugars.
Another diabetes-influencing mechanism of cortisol is that chronic stress inhibits healthy insulin metabolism, adding to your ever-rising blood sugar levels. Insulin is a storage hormone that helps you shuttle glucose through your blood and into your tissues. When your body perceives stress, it triggers the release of glucose for fuel and puts storage on hold to focus all efforts on dealing with the current stressor. However, forms of chronic stress such as sleep loss mean that blood sugars remain consistently elevated.
As an indirect mechanism, a lack of sleep can make fat gain more likely by increasing hunger and cravings. Research shows that short sleep triggers an increase in the hunger hormone ghrelin[22]. Equally, studies show that people eat around 350 more calories when they sleep two to three hours less each night[23]. Over time, this can quickly result in accumulated weight gain. Due to the relationship between body fat levels and diabetes, sleep should be a priority if you’re concerned about your blood sugars.
Here are five ways you can instantly achieve a better night’s sleep:
- Take a warm shower or bath before bed to help cool your core temperature and drift off to sleep more easily.
- Create a hard cut-off time for stimulants like caffeine and nicotine. At least six hours before bedtime should be the minimum.
- Make sure your room is cool, dark, and quiet to help you sleep uninterrupted.
- Create a consistent sleep and wake schedule, even on weekends.
- Dim your home in the hours leading to sleep, as darkness acts as a cue for sleep.
The blood sugar solution
While most people understand the relevance of lifestyle and behavioural change in preventing metabolic diseases like type 2 diabetes, there are often many misconceptions regarding the underlying mechanisms. However, by shedding light on the scientific reasoning behind the advice, more people may recognise the benefits and learn how to apply positive changes to improve long-term health.
Key takeaways
- Weight loss reverses type 2 diabetes in overweight individuals by reducing liver and pancreas fat content.
- Exercise helps you manage type 2 diabetes by increasing insulin sensitivity and your body’s glucose storage capacity over time.
- Diet’s primary role in diabetes is to facilitate weight loss through a calorie deficit.
- Sleep loss is a form of stress that can impact your blood sugar levels by increasing glucose production and reducing insulin sensitivity.
- If you’re concerned about your blood sugars, aligning your lifestyle habits with your health is vital.
