Glucose is our body’s main source of energy. It fuels our cells, brain, and muscles. But when it’s lacking, the body reacts immediately. Do you suddenly feel tired, irritable, or sweaty for no apparent reason? These could be signs of hypoglycemia, a drop in blood sugar below 0.7 g/L (instead of 70 mg/dL, the measurement commonly used in France).
If mild, hypoglycemia may go unnoticed or be quickly corrected with sugar. But if severe, it can lead to dangerous complications, even loss of consciousness. Here are 12 warning signs.

Twelve Signs You Shouldn’t Ignore

Sudden and excessive sweating

Do you sweat even when it’s not hot? Hypoglycemia triggers the release of adrenaline, which stimulates sweating. This often happens before meals or at night, especially in people with diabetes.

What to do?
Quickly eat something sweet like a sugar cube, a glass of juice, or some applesauce.

Irritability and nervousness.
Are you suddenly feeling irritable for no reason? Hypoglycemia triggers the release of cortisol and adrenaline, causing mood swings and unusual irritability.

What to do?
Eat a carbohydrate-rich snack to stabilize your blood sugar.

Sudden and intense hunger:
When the brain is low on glucose, it sends urgent hunger signals. You want to eat right away, even if you’ve just eaten.

What to do?
Choose foods with a moderate glycemic index, such as fruit or whole grains, to avoid a rapid drop in blood sugar levels.

Nightmares and restless sleep

Nocturnal hypoglycemia can lead to vivid nightmares, sudden awakenings with sweating, or a feeling of discomfort.

What to do?
Eat a light snack before bed, especially if you tend to suffer from nocturnal hypoglycemia.

Difficulty concentrating:
The brain requires glucose to function. Too low a level leads to difficulty concentrating, frequent forgetfulness, and a feeling of mental fogginess.

What to do?
Take a break and eat a rapidly absorbed glucose source, like a piece of fruit or a sugar cube.

Vertigo and dizziness

Low blood sugar can affect your balance and cause dizziness. This can be worsened by dehydration.

What to do?
Stay hydrated and eat a sugary snack to stabilize your glucose levels.

Tremors and a feeling of weakness
Low blood sugar triggers a stress response that manifests as tremors, especially in the hands.

What to do?
Quickly eat something sweet and rest for a few minutes.

Vision problems

Blurred vision, appearance of black spots, difficulty seeing clearly… A drop in blood sugar affects eye function and can cause these symptoms.

What to do?
Sit down and eat something sweet while monitoring the progression of your symptoms.

Language disorders:
When the brain is deprived of glucose, it has difficulty coordinating certain functions, such as language. You may have difficulty forming sentences or slurring your speech.

What to do?
Don’t panic and try to stick with a sugar source.

Insomnia and frequent night awakenings
Low blood sugar levels at night can disrupt sleep and cause sudden awakenings with palpitations or a feeling of faintness.

What to do?
Eat a balanced diet and avoid consuming too many sugary meals before bed.

Irregular Heartbeat and Heartburn
Low blood sugar activates the nervous system, causing the heart to race and possibly feel like it’s beating faster than usual.

What to do?
Lie down, breathe deeply, and eat something sweet to stabilize your blood sugar.

Risk of fainting, convulsions and coma

In severe cases, untreated hypoglycemia can lead to loss of consciousness or even coma. This particularly affects people with diabetes undergoing treatment.

What to do?
If you witness someone fainting due to severe hypoglycemia, contact emergency services immediately (SAMU: 15 or 112).

How can you prevent hypoglycemia?
To avoid these symptoms, you need to adopt good eating habits and monitor your blood sugar levels, especially if you’re prone to blood sugar fluctuations.

Some tips:

Don’t skip meals and choose foods rich in fiber and protein.
Avoid excess simple sugars, which cause blood sugar spikes and drops.
If you have diabetes, check your blood sugar levels regularly and adjust your diet accordingly.
Always carry a snack, such as a piece of fruit or a handful of almonds, just in case.
Hypoglycemia is a common but often overlooked condition. Recognizing the signs early helps prevent complications and respond quickly. If you experience these symptoms frequently, consult a doctor to identify the cause and adjust your lifestyle.