How to lower blood sugar?

Blood sugar is the level of glucose, or sugar, in the blood at a given moment. This glucose level is essential for our body to function optimally, since cells use glucose as a source of energy.

Blood sugar is measured in millimoles per litre of blood (mmol/L), milligrams per decilitre of blood (mg/dL) or grams per litre of blood (g/L). The glucose level fluctuates throughout the day and night, affected by factors such as diet, physical activity, certain medications, illness and stress.

Diabetes and blood sugar:

Diabetes is a metabolic condition linked to chronic hyperglycaemia
Other types of diabetes exist:

• Gestational diabetes develops in pregnant women;
• MODY diabetes is a genetic abnormality that causes abnormal insulin secretion.

The glycaemic index (GI) is a tool that ranks foods according to their impact on blood sugar after eating. It is established by comparing the effect of a food on blood sugar with that of glucose, which serves as the reference with a GI set at 100.

Foods are ranked by their GI, which ranges from 0 to 115. A high GI means a food raises blood sugar quickly, which requires the pancreas to produce more insulin. For example, white bread has a GI of 70, while radish is at 15.

How foods are prepared and cooked, their form and their combination with other nutrients affect their GI. Steaming, for example, can lower the GI, while overcooking or turning food into liquid can raise it. In addition, including foods rich in fibre, protein and good fats in a meal can lower that meal’s glycaemic load.

Measuring fasting blood sugar plays an essential role in assessing metabolic health. For a healthy person, there is a specific range within which fasting blood sugar must fall to be considered a normal blood sugar level.

Typically, a normal fasting blood sugar level ranges from 0.70 to 1.10 grams of glucose per litre of blood. This range is internationally recognised as the norm for healthy adults.

It is important to stress that these values must be measured after a period of at least 8 hours without eating to ensure reliable results.

A fasting blood sugar level above 1.10 grams of glucose per litre of blood indicates hyperglycaemia. Moderate hyperglycaemia is defined by a level between 1.10 and 1.25 grams of glucose per litre of blood. By contrast, a level above 1.26 grams of glucose per litre of blood signals chronic hyperglycaemia, which may indicate the presence of diabetes.

Monitoring these levels is vital because chronic hyperglycaemia can cause severe long-term complications affecting important organs such as the eyes, heart and feet.

Hypoglycaemia is defined as an abnormally low level of glucose in the blood. Several factors can be behind it, the main cause being diabetes treatment, in particular the use of insulin or other medications that lower glucose levels.

Taking these medications without adequate food intake, or combining them with intense physical exercise, can cause an excessive drop in blood glucose.

Apart from medications, serious illnesses or organ dysfunction can also cause hypoglycaemia. Conditions such as chronic kidney failure, heart failure, cancer or sepsis can lead to hypoglycaemia, particularly in seriously ill patients.

Endocrine disorders, such as insulinoma (an insulin-producing tumour of the pancreas) or adrenal insufficiency (Addison’s disease), although rare, are notable causes of hypoglycaemia. Insulinoma, in particular, can trigger hypoglycaemic episodes after periods of fasting or exercise.

Certain less common factors, such as bariatric surgery for weight loss, carbohydrate sensitivities, or the use of certain non-diabetic medications (such as high doses of aspirin in children), can also lead to hypoglycaemia.

Hypoglycaemia, also known as low blood sugar, shows up through various symptoms whose intensity and nature can vary. These symptoms are often grouped by severity level.

This first level, known as mild hypoglycaemia, is characterised by adrenergic and autonomic symptoms, such as excessive sweating, nervousness, tremors, a feeling of heat, nausea, heart palpitations and intense hunger. These signs generally result from the nervous system’s response to the drop in blood glucose.

Level 2 hypoglycaemia is considered more severe. It shows up through neuroglycopenic symptoms, indicating a lack of glucose for the brain. These symptoms include difficulty concentrating, fatigue, speech and behavioural disturbances, psychiatric symptoms, as well as motor disorders such as hyperactivity, coordination problems, tremors, headaches and visual disturbances such as double or blurred vision.

Level 3 hypoglycaemia, or severe hypoglycaemia, is the most serious form of this condition. It can cause loss of consciousness or coma, because the brain does not receive enough glucose to function optimally. Symptoms include confusion, agitation, seizures and, in the most severe cases, hypoglycaemic coma. Immediate medical intervention is essential to prevent permanent brain damage or death.

Hyperglycaemia is characterised by an abnormally high level of glucose in the blood. This condition can be triggered by several key factors:

A major cause of hyperglycaemia is insulin deficiency or ineffectiveness. In cases of diabetes, whether type 1 or type 2, the pancreas does not produce enough insulin, or the body’s cells do not respond adequately to this hormone. This prevents glucose from entering the cells, causing it to build up in the blood.

Stress, whether physical or psychological, can also cause temporary hyperglycaemia. Serious illnesses such as flu or pneumonia, or severe inflammatory conditions such as a heart attack or major surgery, can stimulate the release of hormones such as adrenaline and cortisol, leading to a rise in blood glucose.

Certain medications can also cause hyperglycaemia. Corticosteroids, certain types of antidepressants and antipsychotics are known to raise glucose levels.

Similarly, missing or incorrectly administering antidiabetic medications, including insulin, can lead to hyperglycaemia.

Excessive consumption of sugar and carbohydrates is another common cause. Large meals rich in carbohydrates, particularly those containing high glycaemic index foods, can cause a rapid rise in blood glucose.

The absence or significant reduction of physical activity also plays an important role. A sedentary lifestyle can reduce insulin sensitivity and raise blood glucose levels.

Finally, factors such as obesity, high blood pressure and a family history of diabetes can also increase the risk of hyperglycaemia, particularly in the context of type 2 diabetes.

Hyperglycaemia is defined by a high level of glucose in the blood, and it shows up through various symptoms whose intensity and nature can vary.

• The most common initial symptoms include intense thirst and a dry mouth, early signs of a high blood sugar level. This increased thirst comes with more frequent and larger volumes of urine, a phenomenon called polyuria.
• Marked fatigue and drowsiness are also common, resulting from the lack of glucose available for energy, which leads to a feeling of weariness and lack of energy.
• Blurred vision is another usual symptom, caused by variations in blood glucose.
• Despite the rise in blood sugar, excessive hunger can also be felt, as the body tries to make up for the shortage of glucose available to the cells.
• Less immediate but significant symptoms include headaches, cramps, abdominal pain and nausea, occurring as hyperglycaemia worsens.

If left untreated, chronic hyperglycaemia can lead to serious complications, such as recurrent infections, slow healing and unexpected weight loss.

In extreme situations, it can result in a hyperosmolar hyperglycaemic state, a medical emergency characterised by a high concentration of glucose in the blood and changes in mental state without acidosis, requiring immediate intervention.

The treatment of hypoglycaemia, also known as low blood sugar, varies according to the severity of symptoms and the individual’s ability to manage it themselves. Here are the recommended steps for managing mild to moderate hypoglycaemia, as well as severe hypoglycaemia.

For mild to moderate hypoglycaemia, the main treatment relies on a supply of fast-absorbing carbohydrates. It is suggested to consume 15 grams of carbohydrates and wait 15 minutes before checking blood sugar again. If it remains low, the process should be repeated until blood sugar returns to normal.

Here are some recommended sources of carbohydrates:

• 1 tablespoon (15 ml) of table sugar dissolved in water;
• three quarters of a cup (180 ml) of non-diet soda or fruit juice;
• 1 tablespoon of honey or maple syrup;
• 15 to 20 grams of sweets, such as 6 Life Savers or 2 rolls of Rockets.

If the next meal is more than an hour away, it is wise to have a snack made up of 15 grams of carbohydrates and a source of protein, for example a slice of bread with 30 grams of cheese.

In the case of severe hypoglycaemia, where the person is unconscious or unable to eat, a rapid response is essential. Those around them must administer glucagon, a hormone that quickly raises blood sugar. Glucagon can be given by subcutaneous injection or by nasal inhalation, and it generally takes effect within 5 to 15 minutes.

After giving glucagon, it is essential to immediately give the person at least 15 grams of sugar and to monitor their blood sugar regularly. If the person does not regain consciousness within 10 minutes of the injection, a second dose of glucagon may be needed, and it is urgent to contact emergency services.

It is essential for people prone to hypoglycaemia to always have easily accessible carbohydrates and for those around them to be well informed about emergency procedures. Setting up an action plan with a healthcare professional can also help prevent and effectively manage hypoglycaemic episodes.

Managing hyperglycaemia, or high blood sugar, varies according to the severity of the condition, the type of diabetes diagnosed and any complications. The key elements of treatment include:

• Hydration: Rehydration is essential, especially in the case of hyperosmolar hyperglycaemic syndrome. Intravenous (IV) administration of a 0.9% saline solution helps rebalance the body’s fluids and electrolytes. The amount of IV fluids is adjusted to the patient’s condition.
• Insulin: To lower blood sugar effectively, insulin administration is essential. In severe hyperglycaemia, insulin is first given IV, then as a continuous infusion. The recommended initial dose is 0.1 unit/kg as a bolus, followed by an infusion of 0.1 unit/kg/hour.

It is essential to correct any hypokalaemia before starting IV insulin therapy.

• Antihyperglycaemic medications: For people with type 2 diabetes, treatment may begin with non-insulin medications such as metformin, GLP-1 receptor agonists, DPP-4 inhibitors or SGLT-2 inhibitors, alone or in combination with insulin, depending on the patient’s specific needs.
• Lifestyle changes: Adapting your diet and increasing your physical activity are fundamental to managing blood sugar over the long term. A diet rich in fibre and low glycaemic index carbohydrates, combined with a regular exercise routine, helps stabilise blood sugar and prevents diabetes-related complications.
• Monitoring and adjustments: Regular monitoring of blood sugar and haemoglobin A1c (HbA1c) is essential to personalise treatment. Blood sugar targets are tailored to each individual and treatments are reassessed every 3 to 6 months to make sure they are effective.
• Treatment of complications: In the case of severe hyperglycaemia, it is essential to address potential complications such as heart failure, kidney failure and infections. Medications such as renin-angiotensin-aldosterone system blockers, statins and aspirin may be prescribed to prevent these complications.

A high blood sugar level, or hyperglycaemia, especially when persistent, can lead to serious and lasting health consequences. Let us look at the main complications linked to uncontrolled hyperglycaemia.

Chronic hyperglycaemia considerably raises the risk of developing cardiovascular diseases, such as heart disease, strokes and arteritis. These complications occur because of deterioration of the blood vessels and increased blood pressure.

Diabetic neuropathy, or nerve damage, is another major complication. Prolonged hyperglycaemia can damage the nerves, causing symptoms such as numbness, tingling, pain, or loss of sensation in the hands and feet.

Kidney problems are also among the possible consequences. Long-term hyperglycaemia can affect the kidneys, leading to kidney failure which, in the most severe cases, may require dialysis or a kidney transplant.

Vision problems are also a major concern. Hyperglycaemia can cause diabetic retinopathy, a condition that can lead to loss of vision and, in the most critical situations, blindness.

The first warning signs of diabetes, often linked to hyperglycaemia, include a set of distinctive symptoms. Among them are increased thirst and excessive hunger, as well as frequent urination.

Other common symptoms are considerable fatigue or loss of energy, blurred vision, and frequent or repeated infections.

A notable change in weight for no obvious reason, cuts and bruises that heal slowly, and sensations of numbness or tingling in the hands or feet are also potential indicators of early diabetes.

A blood sugar level is considered dangerous and indicative of diabetes when it exceeds certain limits. When fasting, a level above 1.26 grams per litre is often considered a sign of chronic hyperglycaemia, which may signal the presence of diabetes. Likewise, a blood sugar level above 2 grams per litre at any time of the day may indicate diabetes.

• Fédération Française des Diabétiques, What is diabetes? (in French).
• Fédération Française des Diabétiques, How to deal with hypoglycaemia? (in French).
• Haute Autorité de Santé (French National Authority for Health), Therapeutic strategy for patients living with type 2 diabetes (in French).
• EFSA Panel on Dietetic Products, Nutrition and Allergies (NDA), Scientific Opinion on the substantiation of health claims related to chromium, EFSA Journal.
• European Commission, Regulation (EU) No 432/2012 establishing a list of permitted health claims made on foods.
• World Health Organization, Eastern Mediterranean Regional Office, Physical activity and healthy diet (in French).