Aishwarya Shanker, 24, a design student from Bengaluru, says, “I started to have irregular periods at the age of 17 or 18. I went through several blood tests and sonography through which the doctor confirmed that I had PCOS. I have consistent weight fluctuations and mood swings. It is very difficult to lose weight even though I don’t have a great appetite. Fortunately, my thyroid and blood sugar levels are in control, but my doctor has asked me to be cautious as I was at risk of developing diabetes later in life. To ensure that, I work out regularly and follow a healthy diet.”
Diabetes is a metabolic condition triggered due to inefficient breakdown and absorption of glucose in the blood. It is also loaded with co-morbidities, mainly cardiovascular ones directly linked with our cardiac wellness. There are mainly two types of diabetes – type 1 and type 2. The key agent of diabetes is insulin, the hormone secreted from the pancreas which is mainly responsible for glucose metabolism and the dissipation of energy across our body. Type 1 diabetes is caused when the pancreatic beta cells are unable to secrete insulin and thereby the body is unable to maintain blood sugar balance on its own. Whereas type 2 diabetes is mainly due to insulin resistance, a condition where the insulin secreted is unable to break down excess sugar in the blood due to various reasons including excess visceral fat deposition in the body.
Interestingly, endocrinologists point out that apart from insulin resistance, there are multiple hormonal conditions that either directly or indirectly affect glucose metabolism. Some of them could even trigger diabetes at a later stage in life.
Diabetes and PCOS
“The most common disease of hormonal fluctuation seen in young girls is polycystic ovarian syndrome (PCOS.) In this condition, increased weight gain leads to increased insulin resistance. It comprises irregular menses, obesity, insulin resistance and increased male hormones ie, testosterone. The excess testosterone may show symptoms like male pattern balding and facial hair growth in women. It will probably also show infertility, dyslipidaemia and impaired glucose tolerance which may present as diabetes in a later stage. It is like a spectrum starting from irregular periods to diabetes,” says Dr Mahesh Chavan, endocrinologist, Apollo Hospital, Mumbai.
An article published in the journal, Human Reproduction Open, highlights a study done on 27 women over a period of time (from the age of about 30 up to over 50 years of age.) ‘Women with PCOS developed type 2 diabetes more frequently than women without PCOS (19%, compared with 1% in controls), but all women who did so were heavily overweight. Furthermore, in these women, their fat was distributed mainly around the waist, even in young women,’ the paper says.
It further says, “these results show the importance of early diagnosis of PCOS, and that doctors should monitor weight and waist circumference in all women with PCOS to evaluate the risk for later type 2 diabetes development. Advice should be given to women diagnosed with PCOS to avoid weight gain and thereby decrease the risk for type 2 diabetes development.”
Dr Chavan tells Happiest Health that the endocrine system is an interplay of all the hormones and because hormones are interrelated, they will affect blood sugar levels.
“All the counter-regulatory hormones like glucagon, epinephrine, cortisol and growth hormones can contribute to increased blood sugar levels,” says Dr Tony P Joseph, endocrinologist, Hormone India, Trivandrum.”
There are hormones other than insulin that affect blood sugar levels. Let’s look at them.
Glucagon is a hormone which functions diametrically opposite to insulin when it comes to managing blood sugar. Technically if insulin breaks down blood glucose to release energy and keep blood sugar from rising, it is glucagon that sort of acts as a regulator to ensure that our blood sugar level doesn’t dip too low and cause hypoglycaemia.
The liver stores glucose which is called glycogen. The body often uses this glucose from the liver whenever there is a sudden dip in sugar levels. Glucagon plays a major role in converting glycogen into glucose (glycogenolysis) so that it could be used by the body whenever there is an unexpected dip in blood sugar levels. It also inhibits the further breakdown of blood glucose. Glucagon is released overnight and between meals and is important in maintaining the body’s sugar and energy balance.
“Glucagon is the opposite of insulin. One of the causes of high sugar levels is an increase in glucagon in people with diabetes,” says Dr Joseph.
What other hormones can affect diabetes?
GLP-1, GIP and amylin are the other hormones that regulate mealtime insulin. The overall effect of these hormones is to reduce the production of sugar by the liver during a meal to prevent it from getting too high.
Dr Joseph says that glucagon levels are often not checked and often go unmonitored unless an individual develops extremely serious conditions like glucagonoma, a malignant growth in the islet of the pancreas.
Growth hormones and cortisol
Dr Chavan says, “the major hormones are growth hormone and cortisol hormone. They are the first line of defence against low sugar. Their mechanism includes suppressing the internal insulin or preventing the insulin from acting. Hence, whenever there is an increase in growth hormone levels, it will cause the sugars to climb because the growth hormone is preventing the insulin from performing.”
“Cortisol and growth hormones are released during stressful periods. One of their actions is to increase the glucose production from the liver which leads to high blood sugar levels,” says Dr Joseph.
“Likewise, the cortisol hormone is also a hormone which is responsible for the fight or flight response. So, whenever a person is under threat, cortisol is the first hormone that suppresses the insulin secretion and makes the body ready to either fight or flight.” Cortisol is a steroid hormone secreted from the adrenal gland whereas growth hormones are from the pituitary gland.
“When the disease associated with excess growth hormone happens before puberty, it is called acromegaly; if it happens after puberty, it is called gigantism. It shows symptoms like enlarged hands and small bones. On the other hand, when cortisol is in excess from the pituitary gland and adrenal gland, it is called Cushing disease and Cushing syndrome, respectively. In both these scenarios, the imbalance act against the insulin as they compete against the insulin receptor.”
Sex hormones and diabetes
According to a study by the European Society of Endocrinology, “an imbalance in sex hormones has an important impact on type 2 diabetes mainly through the involvement of visceral adipose tissue. Androgens have an interesting sex-dimorphic association with type 2 diabetes since hyperandrogenism in females and hypogonadism in males are risk factors for type 2 diabetes.”
Hyperthyroidism is a condition where there is an excess of thyroid hormone which in turn has excessive resistance to insulin. “It can be identified with warm sweaty palms, bulging eyes, weight loss and palpitations,” says Dr Chavan.
According to a study, “thyroid hormones are essential for carbohydrate metabolism. Hyperthyroidism (thyroid hormone excess) may affect the secretion, action and clearance of insulin and many aspects of carbohydrate metabolism and thus lead to hyperglycemia. On the contrary, hypothyroidism (thyroid hormone deficiency) may also interfere with the action and metabolism of insulin and induce insulin resistance.”