Understanding the link between diabetes and weight gain

In the UK, current stats show that 1 in 4 adults is obese and 2 out of 3 are overweight, with 26 million more people expected to become obese in the next 20 years [1].

The result? A projected increase in the number of people with type 2 diabetes. It’s obvious that there’s a close correlation between weight gain and diabetes, but how does this connection work?

Without further ado, here’s what you should know about diabetes, weight gain and the link between them.

What is diabetes?

First things first: what actually is diabetes? The short answer is that it’s a disease where your blood sugar levels are too high [2].

The long answer is slightly more complicated. You see, when you eat food, your body breaks it down into different components. Most food, though, ends up as glucose, which gets released into your bloodstream [2].

At the same time, your pancreas is producing a hormone called insulin, which your body uses to effectively guide the glucose into your cells, where they can then use the glucose as energy for your body.

But, if you’ve got diabetes, your body either produces insufficient amounts of insulin (or none at all) or isn’t able to use it properly. Your cells may also become unresponsive to insulin. Glucose then remains in your bloodstream, keeping your blood sugar levels elevated. 

When blood sugar levels are too high, you have diabetes.

The issue with having chronically high blood sugar is that it poses harm to your health and increases the chance of developing other serious conditions. High levels of sugar in your bloodstream can damage your blood vessels, inhibiting their ability to carry blood to other parts of your body. This also affects your nerve function [4].

Some of the health complications associated with diabetes include heart attack, stroke, cancer, kidney problems, nerve damage, vision loss and sexual dysfunction [3][4].

You may have also heard of two different kinds of diabetes: type 1 and type 2. The former is where the pancreas isn’t making any insulin and is considered an autoimmune disease (basically where the body mistakenly turns on itself). It often crops up in early life.

The latter is where the body produces very little insulin or the insulin it does make isn’t effective enough to control blood sugar. Usually, it rears its head in adults but is starting to develop in a greater number of children and teenagers [5]. It’s also much more common than type 1 diabetes, affecting 90% of all people with diabetes [6].

What are the symptoms of diabetes?

Between type 1 and type 2 diabetes, there’s a host of common symptoms [7][8][9]. These include:

• Frequent urination, especially at night (this is because your body is attempting to get rid of excess blood sugar through your urine)[10]
• Extreme thirst and hunger
• Fatigue
• Irritability
• Unexplained weight loss
• Blurred vision
• Tingling or numbness in the hands and/or feet
• Slow sore healing or sores that don’t heal at all
• Being more prone to infection and experiencing more of them
• Dry skin

Each type of diabetes also has its own symptoms. People with type 1 diabetes, for example, might experience gastrointestinal issues like tummy troubles, nausea and vomiting, as well as heavy breathing [6][9].

The symptoms of type 1 diabetes also tend to crop up quickly (in some cases, over weeks) and are very conspicuous, whereas those associated with type 2 diabetes come on slowly (often over a period of years) and can be milder, making them a little harder to detect [10].

Can diabetes cause weight gain?

The link between diabetes and weight gain is a multifaceted one. Experts still aren’t exactly sure what causes type 2 diabetes, but they do know that weight is a significant risk factor. 

Being overweight or obese increases the chance of developing type 2 diabetes — particularly if that fat sits around your abdomen [11].

It’s believed that obesity specifically makes up 80-85% of the risk for type 2 diabetes, while there’s also evidence that obesity makes people 80 times more likely to have type 2 diabetes. The reason is that fat alters your body’s ability to react to insulin [1].

But, does it go the other way, too? Can having diabetes make you put on weight?

In many cases, people lose weight if they have either type 1 or type 2 diabetes, without actually trying to. This is because when the body is unable to access glucose for energy, it starts burning fat and muscle instead, leading to unintentional weight loss (and, in some cases, a decrease in muscle mass, too) [12].

On the other hand, some people gain weight. Elevated blood sugar levels can lead to a higher weight because the excess glucose is usually stored as fat. This makes people with diabetes more likely to carry extra weight.

There's also a link between insulin and weight gain. People with type 1 diabetes must take insulin to make up for the fact that their body is unable to produce it. Some people with type 2 diabetes are required to take insulin, too [13]. The thing with insulin is that it often leads to gaining weight [14].

There are many possible explanations for this. One is the fact that insulin is a growth hormone that can increase hunger. As well, people may not reduce their food intake when they start taking insulin and their blood glucose levels return to normal. Simply taking too much insulin can also promote weight gain [15].

It’s important to note that for many people with diabetes who’ve lost a lot of weight, regaining the weight can be part of the recovery process. However, weight gain from taking insulin can become excessive, increasing the likelihood of other health issues, like cardiovascular disease [14].

Can pre-diabetes cause weight gain?

By now you’re familiar with diabetes, but what about pre-diabetes? 

Also known as borderline diabetes, it’s when blood sugar is higher than it should be, but not quite high enough to be considered diabetes. Having pre-diabetes means a greater chance of developing type 2 diabetes, and it currently affects about 7 million people in the UK [16].

Many people with pre-diabetes also have insulin resistance, which is where your cells don’t react to insulin properly and your blood sugar levels rise. Your pancreas then works overtime to produce more insulin, only making the problem worse.

Studies show insulin resistance is closely connected to weight gain [17]. Why? Well, when your cells become resistant to insulin and your blood sugar levels rise, your body stores the excess glucose as fat [18].

Can losing weight help with diabetes management?

Absolutely. Research shows that if you’ve got type 2 diabetes and lose weight — even as little as 5% of your body weight — you can actually help bring your blood sugar levels under control [19][20]. 

Other research has shown that losing weight can even reverse the development of type 2 diabetes. In fact, experts know that weight loss is the biggest factor in putting type 2 diabetes into remission [21].

Losing weight can also improve other things, like mobility, sexual function and overall quality of life.

Plus, being overweight or obese ups the chance of having pre-diabetes [22]. However, there is good evidence to suggest that by losing 5-7% of your body weight, you can lower the risk of developing diabetes [23].

When it comes to type 1 diabetes, things are a little more complicated. This is due to the fact that type 1 diabetes isn’t usually caused by carrying excess weight. In saying that, weight loss can most certainly curb the likelihood of further complications [20].

How to approach weight loss as a diabetic

So, if you’ve got diabetes and want to lose weight, how exactly should you go about it? There are a few ways to approach it.

Maintain a balanced diet

When it comes to your diet, it’s simply about making healthy choices and trying to keep your blood sugar in check — not necessarily restricting yourself to certain foods [24].

Foods to include in your diet include whole grains, fish like salmon and tuna, legumes, low-fat dairy, healthy fats including avocado and nuts, vegetables and whole fruits. It’s best to stick to whole fruit rather than juices because they retain their fibre content and won’t cause a spike in blood sugar levels [25].

At the same time, you also want to avoid processed foods, as well as those high in saturated fat, salt and sugar.

As far as energy intake goes (i.e. how much you should be eating), this all depends on your current weight, your health, your insulin dosage (if you're taking it) and your weight goals. A medical professional, like your GP, or a dietitian can work with you to figure out an ideal target.

Move your body

Exercise is also a crucial part of the equation when it comes to losing weight. If you’ve got diabetes, it also delivers other benefits like decreasing your blood sugar levels, helping to combat insulin resistance by making your body more insulin-sensitive and lowering blood pressure, which is also common among people with diabetes [26][27].

Aim for 150 minutes of moderate-intensity exercise every week, like brisk walking, swimming or even doing chores around the house [28]. Resistance training — like squats, lunges or lifting weights — is also good because it helps to build lean muscle.

If you’re new to exercise, start with smaller increments (like 10 minutes a day) doing lower-intensity exercises (such as a gentle walk around the block) and build up to longer and more intense sessions.

There are a few things to keep in mind when you’re exercising with diabetes.

Check your blood sugar level about 15-30 minutes before you head out. If it's low (below 100 mg/dL) have a small carb-rich snack to raise them. If it's high (above 250 mg/dL) there may be ketones present in your body and exercising won’t be a safe option at that point [29].

You also want to stay adequately hydrated, keep a sugary lolly or glucose tablets with you in case your blood sugar drops, and wear a medical alert bracelet [26].

Avoid crash diets

Crash diets — where you either cut out a particular food or a macronutrient like carbs or severely reduce your calorie intake — aren’t the best approach. 

Not only can they make you regain weight in the long run, but, if you’ve got diabetes, it’s generally not advisable to choose a diet at random without medical guidance [20]. This is especially the case if you’re taking insulin.

One study has also shown that diets that are incredibly low in calories can actually induce insulin resistance and even diabetes itself [30].

Jump on board a dedicated weight loss programme

If you’d prefer a helping hand from a professional, consider Juniper’s Weight Reset Programme.

The programme combines guidance from a team of health coaches, continual medical consultations, health tracking so you can measure your progress, access to a private weight loss community, and weight loss medication.

You can kickstart your weight loss journey with Wegovy or Mounjaro, two groundbreaking weight loss injections that mimic the GLP-1 and GIP hormone respectively to help control cravings, delay stomach emptying, and keep you feeling fuller for longer.

Plus, we have a team of expert dietitians and health coaches you can consult with, to help you work through any challenges you're experiencing during your weight management journey. This holistic approach sets you up for sustained weight loss, rather than a quick-fix solution.

In short, you’ll have everything you need to lose weight safely and sustainably, helping you achieve a healthy weight and keep it for good.

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