Type 2 diabetes is associated with several other metabolic abnormalities, such as central obesity, hypertension, and dyslipidemia, which contributes to the very high rate of cardiovascular morbidity and mortality.
The primary pathologic defects in diabetes include: (1)
- Excessive hepatic glucose production
- Peripheral insulin resistance
- Defective beta-cell secretory function
According to the International Diabetes Federation, over 400 million people were living with diabetes as of 2015.
There are three major types of diabetes:
- Type 1
- Type 2
- Gestational diabetes
Of the three, type 2 is the most common.
The Centers for Disease Control and Prevention estimates that 90% of people around the world diagnosed with diabetes have type 2 diabetes.
In this condition, the pancreas makes insulin, but the cells are not able to use the insulin as well as they should. This is what experts call “insulin resistance.”
Initially, the pancreas makes more insulin to try to move glucose into the cells. But eventually, it fails to keep up and the sugar builds up in the bloodstream, leading to a high blood sugar level.
A number of people with type 2 diabetes are not even aware they have the disease, and this can contribute to various health complications associated with it. According to the American Diabetes Association, 4 out of 10 at-risk adults believe that they have no risk for diabetes.(2)
This makes it even more important to know the risk factors associated with type 2 diabetes.
Risk factors for type 2 diabetes can be categorized as modifiable and non-modifiable. While you cannot do much about the non-modifiable risk factors, there are several others that you can control in order to prevent the development of this disease.
Here are 10 risk factors for type 2 diabetes.
1. Family History
Family history is a known predictor of diabetes prevalence in the US adult population.(3) Your risk of developing type 2 diabetes is elevated if one of your parents or a sibling suffers from it.
According to the American Diabetes Association, your risk of ending up with diabetes is:
- 1 in 7 if one of your parents was diagnosed with diabetes before the age of 50
- 1 in 13 if one of your parents was diagnosed with diabetes after the age of 50
- 1 in 2 if both your parents have diabetes
When combined with other factors that may trigger diabetes (such as unsuitable diet and exposure to certain viruses),(4)(5)(6) your risk of developing this disease increases. Although you cannot change your family history or genetic predisposition, you can decrease your risk for diabetes by avoiding the triggers.
2. Race or Ethnic Background
Aside from family history, people belonging to certain races or ethnicities are more prone to developing type 2 diabetes. Hispanics, African-Americans, Hawaiians, Native Americans, and Asians are at an increased risk of developing this condition.(7)
A 2016 study published in Diabetes Care, reports that the risk of diabetes is significantly higher among Asians, Hispanics, and blacks than among whites, before and after taking into account differences in body mass index.
So, if you are African-American, Asian, Latino/Hispanic, Native American, or Pacific Islander descent, consider making necessary lifestyle changes in order to reduce the risk.
Your risk of type 2 diabetes increases as you get older. It usually occurs in middle-aged adults after reaching the age of 45. This can be due to the fact that people tend to exercise less, lose muscle mass, and gain weight as they grow older.
In a 2010 retrospective study looking at data from 1988 to 2006, the authors found that the prevalence of diabetes in people who were 65 years and older was 17.7%, as compared with 7.8% in those aged between 20 and 64 years, and 6.8% in 12–19-year-olds.(8)
More and more children, adolescents, and younger adults are falling prey of type 2 diabetes nowadays, mainly due to unhealthy lifestyle choices.
Since the mid-1990s, there has been an increase in the occurrence of type 2 diabetes in children and adolescents worldwide. Childhood obesity is the most common risk factor for developing this disease at an early age.(9)(10)
Health experts recommend that from the age of 40, all adults should have their blood sugar level checked every few months. If your risk for diabetes is higher due to race, family history, weight, and other risk factors, it is recommended to start screening earlier.(8) Early diagnosis is the key to preventing or managing type 2 diabetes.
4. History of Gestational Diabetes
If you developed diabetes during pregnancy (gestational diabetes), then you are at an increased risk for type 2 diabetes.
Women diagnosed with gestational diabetes during pregnancy face a significantly higher risk of developing type 2 diabetes in the future.(11)
In fact, in a study conducted in 2008, it was shown that 18.9% of women with a history of gestational diabetes were diagnosed with type 2 diabetes within nine years after the initial diagnosis. In contrast, only 2.0% of women without gestational diabetes were diagnosed with type 2 diabetes in the same timeframe.(12)
This is a modifiable risk factor, and you can decrease the risk by leading an active lifestyle and maintaining healthy body weight. A 2016 study revealed that lifestyle and nutrition counseling reduced the incidence of gestational diabetes by 39%.(13)
5. Excessive Body Weight or Obesity
Being overweight or obese increases the likelihood of developing type 2 diabetes. It has been found that the prevalence of diabetes increases with increasing weight classes. In fact, nearly half of adults with diabetes in the United States are considered obese.(5)
There are certain proteins and hormones generated by adipose tissue or fat, which have been shown to contribute to insulin resistance. These bioactive molecules can also cause an inflammatory response, which further leads to increased risk for diabetes.(14)(15)
This inflammatory response stresses the inner part of individual cells called endoplasmic reticulum (ER). When the ER has more nutrients to process than it can handle, it causes the cells to dampen down the insulin receptors on the cell surface, thus leading to persistently high concentrations of glucose in the blood.
Moreover, if your body stores fat primarily in your abdomen, your risk of type 2 diabetes is greater than when it stores fat elsewhere (like hips and thighs). One good thing about this risk factor is that by losing 5% to 7% of your body weight, you can reduce your susceptibility to type 2 diabetes.
6. Physical Inactivity
A major modifiable risk factor associated with type 2 diabetes is physical inactivity. The less physically active you are, the more chances you have of developing this condition. Being physically active has numerous benefits. For instance, physical activity promotes weight loss, uses up glucose as energy, and makes the cells more sensitive to insulin.
A 2011 study published in Medicine & Science in Sports & Exercise found that significantly decreasing regular physical activity plays a role in impaired glycemic control. This finding suggests that inactivity may be a contributing factor in the development of type 2 diabetes.(16)
Excessive screen time (TV or computer) affects the risk for type 2 diabetes, along with high blood pressure, elevated cholesterol levels, and obesity, in children as well as in adults.
Looking at data from 1999 to 2004, it was found that the odds of children developing metabolic syndrome were 3 times higher in those who spent at least 5 hours of screen time a day as compared to those with 1 hour a day or less of screen time.(17)
The good news is that you can avoid ending up with type 2 diabetes due to physical inactivity by taking a few effective measures.
Exercising for just 30 minutes a day 5 days a week – that’s only 150 minutes of aerobic exercise each week – can significantly reduce your risk for type 2 diabetes, heart disease, and high cholesterol. Strength training 2–3 days a week can also help prevent diabetes and other chronic medical conditions.(18)
7. High Blood Pressure (Hypertension)
High blood pressure can cause significant damage to the cardiovascular system. If left untreated, high blood pressure may also lead to the development of diabetes.
Participants in a 2005 study, who had an established diagnosis of hypertension, were more likely to develop diabetes than those who were not previously diagnosed with hypertension.(19)
The combination of hypertension and type 2 diabetes significantly raises your risk of having a heart attack or stroke. In a study evaluating health-related quality of life (HRQOL) in people with diabetes and hypertension, it was shown that both diabetes and hypertension impair HRQOL. Further reduction of HRQOL was found in those who suffered from hypertension as well as diabetes.(20)
If your blood pressure is running high, take it seriously and follow your doctor’s advice to keep it in check.
8. Abnormal Cholesterol (Lipid) Levels
A low level of high-density lipoproteins (HDL or good” cholesterol) and high triglycerides can increase your risk for type 2 diabetes and cardiovascular disease.
A 2007 study showed that excess cellular cholesterol has a direct role in pancreatic islet dysfunction, which can lead to type 2 diabetes.(21)
Some studies have linked increased risk for type 2 diabetes with the use of statins (a medication class used to treat high cholesterol). Other studies have disclaimed the role of statins in diabetes risk due to the known effects of cholesterol on insulin secretion. Researchers concluded that it’s likely that a person’s LDL level is associated with diabetes risk, rather than an effect of the statins.(21)(22)(23)
To maintain healthy cholesterol levels, a healthy eating plan, consistent aerobic physical activity, and a healthy weight can be of great help. Not smoking can also help maintain healthy cholesterol levels.(23)
Prediabetes, a milder form of the condition, is an obvious risk factor for developing type 2 diabetes. Prediabetes is defined as blood glucose levels above normal but below diabetes thresholds.(24)
A 2012 study published in Lancet reports that people with prediabetes are at increased risk for development of diabetes. There is mounting evidence suggesting that damage to kidneys and nerves is present even at the prediabetes stage.(24)
Lifestyle modification, with a goal of at least 7% weight reduction and 150 minutes of moderate-intensity physical activity, is the cornerstone of diabetes prevention with evidence of a 40% to 70% relative risk reduction.(25)
Prediabetes can be easily diagnosed with a simple blood test. If you have it, it is recommended to become more active and lose extra body weight. Also, opt for a healthy diet and follow the suggestions given by your doctor.
10. Polycystic Ovary Syndrome (PCOS)
Polycystic ovary syndrome (PCOS) has been identified as a risk factor for type 2 diabetes. PCOS is associated with insulin resistance, which is the main cause of this risk.(26) Women with PCOS experience symptoms like irregular menstrual cycle, excess hair growth, and obesity.
A 2004 study published in Minerva Ginecologica reports that women with PCOS have a 5 to 10 fold risk for developing type 2 diabetes, as compared with women who do not have PCOS. The same study found evidence that PCOS is not only associated with insulin resistance but may also result in beta-cell dysfunction.(26)
A 2012 study published in Diabetes also confirms that the risk of type 2 diabetes is markedly elevated in women with PCOS in middle age; this reinforces the need for routine screening for diabetes in PCOS patients.(27)
Tips to Prevent Type 2 Diabetes
- Eat healthy by choosing foods low in fat and calories, and high in fiber.
- Include more fruits, vegetables, and whole grains in your diet.
- Replace full-fat dairy products with low-fat versions.
- Choose healthy unsaturated fats, limit saturated fats, and limit or avoid trans fats.
- While eating, always watch your food portions and try to eat small meals 4 or 5 times a day.
- Indulge in at least 30 minutes of moderate physical activity every day.
- If you’re overweight, take the necessary steps to lose the extra pounds.
- Replace juice and soda with water infused with fresh fruit.
- Quit smoking and excess drinking.
- Watch your blood pressure level and take steps to keep it under control.
- Reduce your risk of cardiovascular disease.
- See your doctor for regular checkups. It is highly recommended to regularly check your blood glucose, blood pressure, and blood cholesterol levels.
Expert Answers (Q&A)
Answered by Dr. Leonardo Bandeira, MD (Endocrinologist)
Is it possible to reverse Type 2 diabetes?
Type 2 diabetes can be controlled and high blood sugar can be reversed, at least temporarily, with treatment. It does not mean that the disease has a cure. In the last decade, several medications, with several mechanisms of action, have been developed, which have facilitated in disease control.
Are insulin injections necessary for a person with Type 2 diabetes?
Not usually. In type 2 diabetes the pancreas still produces insulin. The problem is that insulin does not act properly, and this is directly linked to being overweight. The treatment should be based on lifestyle changes and medications that reduce blood sugar and help lose weight.
However, with the progression of the disease, in patients with poor control, the pancreas produce less and less insulin. So, in some cases, eventually, insulin may be necessary.
What should be an ideal diet plan for a patient with Type 2 diabetes?
Meal plans should be individualized. As recommended by the American Diabetes Association (ADA), carbohydrate intake should emphasize on sources that are high in fiber, including vegetables, fruits, legumes, whole grains, as well as dairy products.
Foods and beverages with added sugar (including fruit juices) should be avoided. A Mediterranean-style diet rich in monounsaturated and polyunsaturated fats may be considered, and eating foods rich in long-chain n-3 fatty acids, such as fatty fish, nuts, and seeds is recommended.
The use of non-nutritive sweeteners is preferred over sugar sweeteners, but overall, people are encouraged to increase water intake.
What is the best way to lower blood sugar levels?
Treatment to lower blood glucose should be based on a set of strategies, not just a single one. This should include lifestyle changes (diet, physical activity, smoking cessation), medications, and insulin in some cases. Weight control is an essential part of the therapy.
What precautions should be taken to prevent prediabetes from taking the form of Type 2 diabetes?
Prevention of Type 2 diabetes should include lifestyle changes (diet, physical activity, smoking cessation), and medications that help control blood glucose and reduce weight. Also, monitor your risk for developing Type 2 diabetes risk by getting at least an annual assessment.
Please enlighten our readers on how to lead a healthy life with Type 2 diabetes.
Leading a healthy life is the key to better control in patients with Type 2 diabetes. As mentioned earlier, it is important to follow a proper diet, do physical activity regularly, and stop smoking. Adherence to medications is critical in addition to periodic follow-up with a trained physician and nutritionist.
About Dr. Leonardo Bandeira, MD: Dr. Bandeira graduated from the Federal University of Pernambuco, Recife, Brazil. He was a resident of Internal Medicine at the Brazilian National Health System and completed his fellowship in Endocrinology at Santa Casa, Sao Paulo, Brazil.
He also completed his Postdoctoral Fellowship in Endocrinology at Columbia University Medical Center, New York, NY. Currently, he sees patients in endocrinology clinics, endocrine dynamics tests lab and participates in research groups at Hospital Agamenon Magalhaes in Recife, the Federal University of Sao Paulo and Columbia University in NYC.
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