Obesity and diabetes often co-exist, but their relationship is somewhat complex. Does obesity cause diabetes or does diabetes cause weight gain? In this article we’ll explore this complex but important relationship and what you can do to improve both conditions, as well as your overall health. Although there are several types of diabetes, this article will focus solely on type 2 diabetes.

Does obesity cause diabetes?

More than 90% of people with type 2 diabetes also have overweight or obesity. And excess weight certainly increases the chances of developing diabetes. Studies show that obesity increases the risk of developing diabetes 7-fold in men and 12-fold in women, when compared to persons without excess body weight. But excess body weight is not the only risk factor for developing type 2 diabetes, and not all persons with obesity will go on to develop diabetes. Other risk factors include age, ethnicity, lifestyle factors such as diet and activity level, and having a family history of diabetes. 

How does obesity cause diabetes?

To address this question, let’s first understand a bit more about diabetes and how it develops. Type 2 diabetes is the most common type of diabetes and is defined by increased blood sugar levels that occur as a result of insulin resistance and decreased insulin secretion. Insulin, made and released by the pancreas, is a hormone that regulates blood sugar levels. It does this by taking sugar out of the bloodstream and delivering it into cells, where it is an important source of energy. Muscle and liver cells play an important role as our bodies store glucose there for later use. 

When insulin resistance develops, tissues are less responsive to the action of insulin, so sugar stays in the bloodstream rather than entering cells effectively. The pancreas works to normalize blood sugar levels by pumping out more insulin, and higher levels of insulin can help compensate for its diminished effect. But the cells of the pancreas in people with insulin resistance struggle to keep up with increasing demands; at some point they cannot keep up. There is then insufficient insulin production to overcome the levels of resistance, and blood sugar levels rise. 

Obesity is known to worsen both insulin resistance and insulin secretion. Many studies link obesity to insulin resistance, and many studies support that in obesity there is dysfunction of the pancreatic cells that produce insulin. So these are fundamental ways in which obesity contributes to rising blood sugar levels and ultimately diabetes. Additionally, newer research suggests that changes in gut bacteria (our ‘microbiome’) associated with obesity may play a role, but we don’t yet have all the information we need to fully understand that piece of the puzzle or how it could be a target for intervention. 

On the flipside – does diabetes cause weight gain?

Here too the relationship is complex. When people have very severe diabetes, often before it is diagnosed, they may lose weight. Sugar is not effectively driven into their cells, and the cells do not have the energy they need. But we also know that diabetes can contribute to weight gain. When high levels of insulin are secreted to compensate for insulin resistance, it can contribute to weight gain. This is because insulin not only regulates our blood sugar levels, but it also promotes the storage of fat. So insulin resistance and high levels of insulin can lead to increased fat storage and therefore weight gain.

Additionally, treatments used to control blood sugar in people with diabetes can themselves contribute to weight gain. Some medications that are part of diabetes treatment plans have weight gain as a side effect. This includes insulin, as well as other oral medications. Sulfonylureas (which include glimepiride and glipizide) and thiazolidinediones (which include pioglitazone and rosiglitazone) have weight gain as a potential side effect. All of these medicines can also increase the risk for low blood sugars, which has to be treated by eating sugar, and therefore can also contribute to increased calories. 

For anyone who has a diagnosis of diabetes, it will be important to discuss weight as a health issue with your healthcare providers at the time of starting treatment for diabetes, and if you noticed weight gain since starting treatment. The good news is that there are diabetes treatment options available that do not cause weight gain, and can even help you to lose weight, so a discussion with your healthcare provider about whether those might be appropriate for you can be very helpful. 

What does “diabesity” mean?

Diabesity is a term used to describe the coexistence of both diabetes and obesity. It is based on the idea that the two are linked by similar changes in physiology - insulin resistance and dysfunction of the pancreas. Additionally, both conditions increase the risk of heart disease, a leading cause of death in the United States. Because of this, it is important to consider how diabetes treatment can impact weight and vice versa – treating both conditions, or diabesity, is likely to have more profound effects on overall health.

Would losing weight help your diabetes?

Yes! Losing weight is perhaps the single best thing you can do to manage diabetes. An initial goal of losing 5-10% of your initial body weight is often recommended for patients with diabetes, but studies have shown meaningful improvements in blood sugar levels with even a 2-5% weight loss. Remission of diabetes has even been seen with larger amounts of weight loss (≥ 10-15% of initial body weight) and after bariatric surgery, though the ability to achieve this depends on many factors, including how long a person has had diabetes as well as their ability to maintain the weight loss. 

Weight loss also improves many of the complications that coexist with diabetes. Studies show that weight loss reduces the need for medications to treat high blood pressure and high cholesterol. It also reduces the risk of damage to the kidneys, eyes, and nerves, which can happen with persistently elevated blood sugar levels. 

Is it harder to lose weight with diabetes?

Weight loss is challenging for most people. There is research to suggest that it could be even harder for people with diabetes. This is likely due to that state of insulin resistance and subsequent fat storage that we’ve already discussed. Not to mention the potential for some diabetes medications to cause weight gain or make weight loss more challenging. With that said, there are proven ways to lose weight even for people with diabetes:

• Adopt a healthy, reduced-calorie diet. There is no one best diet for losing weight with diabetes. Studies consistently show that reducing calorie intake is the foundation for losing weight and this is true for persons with diabetes as well. Additionally, consuming a nutritionally-balanced diet is important for both weight loss and diabetes management. Aim to incorporate non-starchy vegetables daily, choose whole grain carbohydrates versus those that are refined or have added sugar, and consume primarily lean protein. And don’t forget about beverages. Drinking sugar-sweetened beverages is only going to increase blood sugar and insulin levels further, making weight loss more challenging.
  

• Increase physical activity level. This is mutually beneficial for losing weight and improving blood sugar levels. If you’re currently inactive, start slow. Just increasing your activity level by 10 minutes per day can be beneficial for your health in many ways. Making regular physical activity a part of your life is essential for weight loss maintenance and diabetes management, so find an activity that you enjoy and a way to make it part of your daily routine. 
  

• Optimize stress levels and sleep. We often focus so much on food and physical activity that we forget about the importance of stress management and sleep for losing weight. Both can also play a role in blood sugar regulation and worsen insulin resistance, so making efforts to reduce your stress levels and improve your sleep are important for diabetes management as well. 
  

• Review your treatment plan with your healthcare provider. If you’re taking medications for diabetes that have weight gain potential or you have noticed that you’re gaining weight after starting on diabetes treatment, it is important to discuss options with your healthcare provider. It is not safe to suddenly stop taking these medications, but there are alternatives that may be an option for you and could help you to lose weight while also improving your blood sugar. These include metformin, glucagon-like peptide-1 receptor agonists such as Ozempic^Ⓡ and Victoza^Ⓡ, and sodium-glucose cotransporter-2 inhibitors such as Invokana^Ⓡ, Farxiga^Ⓡ, and Jardiance^Ⓡ. 
  

• Seek additional support. If you’re adopting healthier habits but still having difficulty losing weight, it may be time to seek professional help. Registered Dietitians are extremely valuable for patients who are trying to lose weight and manage diabetes. There are also medical providers who have expertise in treating overweight and obesity using evidence-based tools aimed at addressing biological factors that may be interfering with your success. This may include the use of weight loss medications, some of which can also be beneficial for improving blood sugar levels and therefore help you control diabetes while losing weight. 
  

How Form Health can help you with your weight loss journey

At Form Health, we take co-existing conditions like diabetes into consideration when crafting personalized weight loss plans. Our Board Certified Doctors and Registered Dietitians have expertise in formulating treatment plans to treat both obesity and diabetes, which may include the use of FDA-approved medications that can promote weight loss while lowering blood sugar. If you’re living with diabetes and interested in seeking medical care for weight management, give Form a try! We can help by developing a personalized path aimed to improve your diabetes numbers and help you lose weight. Take our quiz to see if the Form program is right for you!

Ozempic® and Victoza® are registered trademarks of Novo Nordisk A

SInvokana^Ⓡ is a registered trademark of Janssen Pharmaceuticals, Inc