Diabetes mellitus is a metabolic disorder resulting in elevated blood sugar levels. The body may either not produce adequate insulin or might struggle to use the insulin it creates effectively.

Diabetes, fundamentally, is a metabolic disorder characterized by the body's inability to properly regulate blood sugar, or glucose, levels. Metabolism refers to how the body uses and produces energy from food.[1]

For our cells to function and thrive, they need energy, which is primarily derived from glucose. The hormone insulin, produced by the pancreas, plays a pivotal role in this process. It helps cells absorb glucose from the bloodstream. In diabetes, there's a disruption in this process.

Insulin, a vital hormone, facilitates the movement of sugar from the bloodstream into cells, providing them with energy. A malfunction in this process might lead to diabetes. If left unaddressed, prolonged high blood sugar can lead to complications such as nerve, eye, kidney, and other organ damage. However, by gaining knowledge about diabetes and taking preventive or management measures, one can ensure better health outcomes.[2]

Classifications of Diabetes

Diabetes is categorized into several types:

Type 1 Diabetes: Type 1 diabetes, often referred to as juvenile diabetes because of its common onset in childhood, is a chronic condition in which the pancreas produces little to no insulin. Insulin is a vital hormone that allows glucose (sugar) from the food we eat to enter our cells and be converted into energy. [3]

Without sufficient insulin, glucose accumulates in the bloodstream, leading to elevated blood sugar levels, which can cause a range of health complications if left untreated. The precise cause of type 1 diabetes is still a topic of research, but it is generally understood to be an autoimmune condition.

In type 1 diabetes, the immune system mistakenly attacks and destroys the insulin-producing beta cells in the pancreas. Why this autoimmune response occurs is not entirely clear, but it is believed to be a combination of genetic predisposition and environmental factors, possibly including viral infections. [4]

Type 2 Diabetes: Type 2 diabetes is a chronic medical condition characterized by the body's inability to use insulin effectively. While insulin is produced by the pancreas, in type 2 diabetes, the body either resists its effects or doesn't produce enough of it, resulting in elevated blood sugar levels. This condition is the most common form of diabetes, affecting millions of people worldwide. [5]

Unlike type 1 diabetes, which is typically diagnosed in childhood and is an autoimmune condition, type 2 diabetes often develops later in life and is closely linked to lifestyle factors. These lifestyle factors include nutrition that is healthy for blood sugar control, meal timing, stress, sleep, exercise, and resistance training. However, genetics also play a significant role in its onset, meaning a family history of type 2 diabetes increases one's risk. A family history does not doom a person to become a type 2 diabetic; it gives them a warning that they are at increased risk and need to focus on a healthy lifestyle in order to avoid becoming a type 2 diabetic.

Several factors contribute to the development of type 2 diabetes. These include being overweight, particularly when the extra weight is carried around the abdomen, trunk and belly. Sedentary lifestyles, characterized by limited physical activity, also elevate the risk. Moreover, certain racial and ethnic groups, including African Americans, Latinos, and Asian Americans, are at a higher risk of developing the condition.[6]

Type 1.5 Diabetes (LADA): Type 1.5 diabetes, also known as Latent Autoimmune Diabetes in Adults (LADA), is a term that has emerged to describe a form of diabetes that shares characteristics of both type 1 and type 2 diabetes. Though not universally recognized as a separate classification, LADA is increasingly acknowledged in the medical community due to its distinct features. [7]

LADA typically presents itself in adulthood, often after the age of 30. Similar to type 1 diabetes, LADA is autoimmune in nature, meaning the body's immune system mistakenly attacks and destroys insulin-producing beta cells in the pancreas. This autoimmune response differentiates it from type 2 diabetes, which is characterized more by insulin resistance.

However, the onset of LADA is typically slower than that of type 1 diabetes. Because of this gradual progression, individuals with LADA might initially be misdiagnosed as having type 2 diabetes, especially since they often do not require insulin right away. Over time, though, as the beta cell function decreases, insulin treatment becomes necessary. [8]

The exact cause of LADA remains uncertain, but like other forms of diabetes, it is believed to be a combination of genetic and environmental factors. Additionally, the same antibodies that are present in type 1 diabetes can often be detected in individuals with LADA, further emphasizing its autoimmune aspect.

Diagnosing LADA can be a bit more challenging due to its similarities with both type 1 and type 2 diabetes. The presence of specific antibodies and the progression of the disease can provide key insights for accurate diagnosis. [9]

Gestational Diabetes: Gestational diabetes is a temporary condition that arises during pregnancy and is characterized by elevated blood sugar levels. It affects a small percentage of pregnant women, typically around the 24th to 28th week, but can occur at any time. While the exact cause is not fully understood, it is believed that the hormones produced by the placenta make a woman's cells more resistant to insulin, leading to higher glucose levels in the bloodstream.

The majority of women suffering from gestational diabetes don't exhibit discernible symptoms. Consequently, screening for this condition has become a standard part of prenatal care. If not managed appropriately, gestational diabetes can pose risks for both the mother and the baby.

For the mother, there's an increased likelihood of having a larger-than-average baby, which can lead to complications during delivery. One of the complication is if the baby grows too big to be safely delivered vaginally, a cesarean section will be necessary for the baby to be born. For the baby, there's a risk of early or premature birth, respiratory issues, and low blood sugar right after birth. These babies might also face a higher risk of obesity and type 2 diabetes later in life. [10] 

For the mother, as a consequence of having gestational diabetes, she has an increased risk of prediabetes or type 2 diabetes later in her life. About 50% of the women who had gestational diabetes develop type 2 diabetes later in life. [11] 

Prediabetes: A Warning Signal

Prediabetes is a condition where blood sugar levels are higher than usual but not elevated enough to diagnose as type 2 diabetes. It arises when cells in the body become less responsive to insulin. Disturbingly, while more than 1 in 3 Americans may have prediabetes, a vast majority (over 80%) remain unaware. [12] 

The lab test value of the Hemoglobin A1C, usually abreviated to A1C, is a big part of what clinically determines the diagnosis of prediabetes or type 2 diabetes.

For the diagnosis of prediabetes, the A1C is in the range of 5.7 - 6.4. 

For the diagnosis of type 2 diabetes, the A1C is in the range of 6.5 and higher.

Symptoms Linked to Diabetes

The manifestation of diabetes is tied to escalating blood sugar levels. These symptoms might vary based on the type of diabetes and individual differences but generally include increased hunger, frequent urination, fatigue, blurry vision, and more. Symptoms can be specific to gender, with men experiencing issues like decreased libido and poor muscle strength, while women may experience vaginal dryness and urinary tract infections. 

For gestational diabetes, many women remain asymptomatic, but in some cases, increased thirst or urination may be noted. [13]

Causes Underlying Diabetes

The origin of diabetes varies with its type:

• Type 1: Although the precise cause remains elusive, a blend of genetic and possibly viral factors might prompt the immune system to attack the pancreas. [14]
• Type 2: A mix of genetic and lifestyle factors contribute to type 2 diabetes. Being overweight or having a family history of diabetes can heighten the risk. [15]  Eating highly refined foods, highly processed foods, nutrient-deficient foods, chronic levels of high stress, poor sleep, sleep disorders like sleep apnea, poor meal timing (e.g. eating a big meal right before bedtime, lots of snacking throughout the day, etc.), a lack of consistent exercise, a lack of strength training, are all factors that contribute to the risk of having type 2 diabetes.
• Type 1.5: This type arises due to an autoimmune attack on the pancreas, similar to type 1.[16]
• Gestational: Hormonal alterations during pregnancy, coupled with weight and genetic factors, can lead to gestational diabetes. [17]

Factors Influencing Diabetes Risk

Several elements can enhance one's susceptibility to diabetes, depending on its type. For instance, having a family history or specific genes can elevate the risk for type 1 diabetes. Factors like age, inactivity, previous gestational diabetes, and certain ethnic backgrounds can increase the likelihood of type 2 diabetes.

In Summary

Diabetes poses considerable health risks, but awareness, early detection, and management can mitigate complications and ensure healthier living.