10 Warning Signs of High Blood Sugar You Can't Afford to Ignore, According to Doctors

According the World Health Organisation, the global diabetes cases have increased four-fold over past decades.
Highlighting how sedentary lifestyles and poor food choices have fueled the diabetes epidemic, WHO Director-General Dr Tedros Adhanom Ghebreyesus said in 2024, "We have seen an alarming rise in diabetes over the past three decades, which reflects the increase in obesity, compounded by the impacts of the marketing of unhealthy food, a lack of physical activity and economic hardship."

However, even before one is diagnosed of diabetes, they might show some very early signs of it which are so subtle that they can often go unnoticed. Talking about this, Dr. Sudhanshu Rai- Metabolic doctor and Sports Physio- revealed the 10 early signs of high blood sugar and insulin resistance one must notice before it’s too late. "Awareness is the first step— listen to your body and take action early," he wrote in the post. Here's what they are:

When your blood sugar levels are high, your "kidneys work overtime to flush excess blood sugar," Dr Rai shared. According to Healthline, "Frequent urination is a symptom of hyperglycemia, or high blood sugar. Diabetes can cause frequent urination, but urinating frequently can also have other causes, such as a urinary tract infection."

Another major sign of diabetes and insulin resistance is when one constantly feel thirsty and drinks more water as the "body tries to replace lost fluids from frequent urination," the doctor said.
According to Medical News Today, "A person with type 1 diabetes is unable to produce insulin. Someone with type 2 diabetes is able to produce insulin, but their body is unable to use it effectively to help glucose enter cells. In either case, glucose from digested food remains in the bloodstream. As the authors of a 2014 article note link: https://pmc.ncbi.nlm.nih.gov/articles/PMC5736956/ , the kidneys excrete some excess glucose through urine. As the glucose draws water into the urine, the body loses more fluid than it should. This results in the person becoming extra thirsty."

Dr Sudhanshu Rai further revealed that blurry vision can also be a sign of diabetes and insulin resistance as "High blood sugar damages tiny blood vessels in the eyes". If left untreated, diabetes can even lead to severe vision impairment over time.

"Poor circulation and high sugar impair healing," says Dr Rai. A 2019 study titled 'The Problem of Wound Healing in Diabetes—From Molecular Pathways to the Design of an Animal Model' states that for people with diabetes, wounds are risky not just because of infection but also because they heal slowly. A weakened immune system makes it easier for infections to become severe, sometimes leading to life-threatening conditions like sepsis. Diabetic patients also face a higher chance of needing tissue removal or even amputation if the wound becomes badly infected or loses blood supply. High blood sugar (hyperglycemia) slows down the body’s natural healing process, making early and intensive treatment essential to prevent wounds from becoming chronic and dangerous.

Since uncontrolled blood sugar levels cause nerve damage in the long run, it leads to tingling in the feet. Some other similar sigs of high blood sugar are burning, and numbness in feet, as per a review on diabetic peripheral neuropathy.

When you have high blood sugar levels or insulin resistance, your "body breaks down muscle and fat for energy," which can cause unexpected weight loss, Dr Rai explained. If you are experiencing sudden weight loss without any particular reason, you should get your health checkup done (especially blood sugar levels checked). Do consult your doctor if you are experiencing one or more symptoms mentioned in this article.

Another subtle early sign of diabetes is "fruity breath odour", Dr Rai said. Explaning this, he further shared, "Ketones appear when the body burns fat for energy".

"High blood sugar weakens immune defenses," Dr Rai said and this leads to constant or recurring infections. An article titled 'Diabetes and infection: review of the epidemiology, mechanisms and principles of treatment' published in 'Diabetologia' in 2024 highlights how people with diabetes are at an increased risk of various infections-- including kidney infections, pneumonia, skin infections-- due to impaired immune response.

Another major red flag of diabetes is Acanthosis nigricans-- a skin condition characterised by dark, thick, velvety patches, usually in body folds like the neck, armpits, or groin. It is often linked to insulin resistance and diabetes, as per the International Journal of Research in Dermatology.

Another red flag for diabetes is when you feel extremely hungry. This happens as "cells starve despite high blood sugar levels," Dr Rai shared. According to the American Diabetes Association, high blood sugar and insulin resistance cause hunger and cravings due to the brain's need for glucose; this in turn creates a cycle that complicates blood sugar management.
[The information presented in this article has been compiled from multiple media and research sources. This content is intended for general awareness and should not be taken as medical advice or a definitive scientific conclusion.]