The Digest

25 million Americans have been diagnosed with Type 2 diabetes, and many of then have children.

This might lead you to wonder whether Type 2 diabetes can be passed from one generation to the next. 

Type 2 diabetes itself cannot be inherited—no child will be born with Type 2 diabetes.

However, it is possible to inherit an "increased risk" of developing Type 2 diabetes.

It’s a fine distinction to make, but one worth exploring.

Type 2 diabetes

Research has shown though that Type 2 diabetes is a complex condition that develops as a result of many factors, including a person’s

• DNA
• Environment
• Gut microbiome

Type 2 diabetes is the most common kind of diabetes, and typically doesn’t develop until later in life.

There are younger people, however, who do get it. 

People with Type 2 diabetes are more likely to experience health issues related to higher blood-glucose levels (e.g. cardiovascular disease and kidney disease).

DNA

Everyone inherits two sets of DNA, one from each of their biological parents.

That DNA is comprised of four letters (A, T, C, and G) which together form a code.

It can be helpful to think of DNA as being similar to a recipe book containing thousands of different recipes. The recipes coded into your DNA tell your body how to make a human being, complete with instructions that dictate your natural hair color and other such traits.

Large-scale genetic studies have shown that people with Type 2 diabetes tend to share patterns in their DNA that aren’t found as often in people without type 2 diabetes.

“It's clear that there's a significant genetic component related to the risks of Type 2 diabetes,” says Dr. Orville Kolterman, Pendulum’s Chief Medical Officer, who also points out that genetic components only seem to explain about 5 percent of the risk for Type 2 diabetes, “...meaning 95 percent of the risk is attributed to other factors.” 

A person’s DNA may affect their biology so that under specific circumstances, they are more likely to develop Type 2 diabetes than not.

So what are the “specific” circumstances, exactly? 

Environmental factors

DNA seldom exclusively dictates a person’s destiny, and this is particularly true for Type 2 diabetes.

A person’s diet has a large influence over their risk of developing Type 2 diabetes, and your diet is largely determined by you.

Every person inherits both socioeconomic and physical environments. These environments can have a large influence on our diets.

For example, if you are born in the United States, you are inheriting an environment in which most people cook, sell, and eat highly-processed westernized foods.

The nutritional quality of your diet can also vary across different socioeconomic backgrounds. The foods we eat, the frequency and amount we eat, and the way we prepare our foods are all habits that are influenced by our environments.

If you are born into an environment that favors high-sugar diets, you are inheriting a higher risk for developing Type 2 diabetes.

The gut microbiome

During childbirth, bacteria and other microbes naturally find their way into a baby’s digestive tract where they will begin forming the gut microbiome.

The gut microbiome helps us in many ways and influences several aspects of our physiology.

Studies in mice and humans suggest that the gut microbiome may affect a person’s body weight, eating habits, and even their risk for developing Type 2 diabetes.

While a person’s microbiome changes over time, the bacteria they are born with is a product of the environment they’re born into. Research on populations around the world have shown that the gut microbiome varies from country to country, indicating that you partially inherit your gut microbiome from the environment you live in.

The heritability of Type 2 diabetes

Just because your relatives have Type 2 diabetes does not guarantee that you will too.

You can change your diet, alter your habits to include more exercise, and take steps to build a healthy microbiome

Read here to learn more about the connection between the gut microbiome and Type 2 diabetes.

If you’re concerned about Type 2 diabetes, or if it runs in your family, talk to your healthcare provider to learn more about your risks.

There are several steps you can take to minimize your chances of developing diabetes, including blood glucose monitoring and tracking your A1C levels.

References:

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