Diabetes (high blood sugar)
Diabetes means blood sugar stays higher than it should. This page explains the symptoms, which tests are used to diagnose it, what treatment and follow-up look like, and when to get help urgently.
What is diabetes?
In diabetes, the level of sugar (glucose) in the blood stays too high. A hormone called insulin has to move sugar from the blood into the cells. In diabetes, either not enough insulin is made or the body does not respond to it well.
There are two main types. In type 1 diabetes, the immune system destroys the cells that make insulin, and the patient needs insulin every day. Type 2 diabetes is more common; the source says it accounts for about 90 to 95 percent of cases. This page is mostly about type 2. There is also gestational diabetes, which usually ends after delivery but keeps the risk of type 2 diabetes higher in the years that follow.
Symptoms
The most common symptoms listed in the source are: heavy tiredness, passing more urine than usual, constant thirst and unexplained weight loss. Blurred vision, slow-healing wounds, and itching or thrush (a fungal infection) are sometimes seen too.
Symptoms appear slowly, and many people with diabetes have none. For this reason the condition can go unnoticed for years. If your risk is high (diabetes in a parent, brother or sister, excess weight, low physical activity, high blood pressure), get tested even without symptoms.
How is it diagnosed?
Diagnosis is by blood test. Based on the CDC source, these are the three common tests and their cut-offs:
| Test | Normal | Prediabetes | Diabetes |
|---|---|---|---|
| HbA1c (average blood sugar over the past two to three months) | Below 5.7% | 5.7 to 6.4% | 6.5% or higher |
| Fasting blood sugar | 99 mg/dL or lower | 100 to 125 | 126 or higher |
| Glucose tolerance test (value at two hours) | below 140 | 140 to 199 | 200 or higher |
A random blood sugar of 200 mg/dL or higher is also listed in the diabetes range in the same source. These cut-offs are general guides. The doctor interprets your number together with your symptoms, history and other tests, and may repeat the test.
Treatment and management
The aim is to keep blood sugar within the range the doctor sets for you and to prevent late complications. The NHS source puts changes to daily habits first:
- Food. Fruit, vegetables, whole grains and pulses; less processed food that is high in salt and sugar. Do not start a very strict, very low-calorie diet without talking to the doctor or a dietitian.
- Activity. The sources recommend at least 150 minutes (two and a half hours) a week of walking or other activity that makes you a little breathless. If you have been inactive for a long time, start slowly and ask the doctor which activity suits you.
- Medicine. If changes to daily habits are not enough, the doctor adds medicine. Only the doctor decides the type and dose. Some patients need insulin at some stage.
The NHS source says that changes to daily habits can sometimes bring blood sugar to a normal level and put the condition into “remission”. This does not happen for everyone and is not a promise that applies to you; the doctor can tell you what is realistic to expect in your situation.
Follow-up and self-care
Diabetes is a long-term condition, and regular follow-up is part of treatment. Based on the NHS source, these checks are usually needed: HbA1c every three to six months, a foot examination, checks of blood pressure, blood fats, weight and kidneys at least once a year, and an eye examination every one or two years. The NIDDK source also recommends a dilated eye examination at least once a year and a dental check once a year. The doctor sets your exact schedule.
A few simple habits help:
- Keep a notebook of your blood sugar and blood pressure readings and bring it to your visit.
- Look at your feet every day. Show the doctor any small sore or blister that does not heal.
- Take medicines on time and as prescribed. If you have a side effect, talk to the doctor instead of stopping the medicine.
- When you see any other doctor, say that you have diabetes and which medicines you take.
Very low and very high blood sugar
Low blood sugar (hypoglycaemia). The NIDDK source says that for many patients a level below 70 mg/dL counts as low, but the threshold differs from person to person and you should ask the doctor. Symptoms: shakiness, cold sweat, hunger, a pounding heart, dizziness, confusion, blurred vision. Very low blood sugar can lead to loss of consciousness and seizures. A person who is awake and able to swallow should have fast-acting sugar straight away and measure again after 15 minutes. If the person is unconscious, give nothing by mouth and call 115 (the emergency number in Iran) at once.
Very high blood sugar and ketoacidosis. Severe thirst, passing a lot of urine, stomach pain, nausea and vomiting, breathing deeper than usual, a fruity or nail-polish smell on the breath, and drowsiness or confusion can be signs of diabetic ketoacidosis, which is an emergency.
When should you call?
Call 115 (the emergency number in Iran) at once if:
- a person with diabetes is unconscious or has had a seizure, or has low blood sugar and is not alert
- the person has signs of ketoacidosis, especially confusion and drowsiness
- the person has chest pain or pressure, sudden shortness of breath, or signs of a stroke (in patients with diabetes and nerve damage, chest pain may not be felt; see the guide “When should I call urgently?”)
See the doctor, or phone for advice, if your blood sugar has been above or below your target several times in a row, a foot sore is not healing, you have developed blurred vision, or you do not know how to take a medicine.
Every patient’s treatment plan is different; ask the doctor about your own situation.
Frequently asked questions
My sugar was high once. Does that mean I have diabetes?
Not necessarily. If the test was done somewhere like a pharmacy or a health fair, the source says a doctor may repeat the test to make sure the result is right. The diagnosis is made by a doctor, not by a single number.
Will I have to take medicine for the rest of my life?
The answer is not the same for everyone. The sources say that changes to daily habits can sometimes bring blood sugar down to a normal level and put the condition into "remission", but this does not happen for everyone, and decisions about medicine are the doctor's. Never reduce or stop a medicine on your own.
What is my target blood sugar?
The doctor sets the target for each patient separately, and it depends on age, medicines and other conditions. The source on low blood sugar also says the threshold can differ from person to person. Ask the doctor for your own number and write it down.
Why do I need a test every few months when I feel fine?
Because high blood sugar often has no clear symptoms, and damage to the eyes, kidneys, nerves and blood vessels develops slowly. Regular tests and check-ups are there to catch a problem early.
Does only sugary food cause diabetes?
No. The sources list risk factors such as excess weight, low physical activity, family history and age. Sweets and sugary drinks raise blood sugar and should be cut down, but they are not the only cause of diabetes.