Does drinking milk increase blood sugar levels: Know about lactose and added sugars

Milk has been a key part of human diets for centuries, providing protein, calcium, vitamins, and essential minerals. Despite these benefits, many people worry about its effect on blood sugar levels. Plain milk naturally contains lactose, a sugar that releases glucose gradually, while flavoured milk and milkshakes often contain added sugars that can cause rapid spikes in blood glucose. Understanding the difference between natural and added sugars is essential for maintaining healthy blood sugar levels. This knowledge is particularly important for individuals managing diabetes, prediabetes, or insulin resistance, helping them make informed dietary choices.Lactose – the natural milk sugarLactose is the naturally occurring sugar in milk, composed of glucose and galactose. Unlike refined sugars found in sweets, soft drinks, or desserts, lactose provides energy alongside valuable nutrients like protein, calcium, vitamin B12, and iodine. Plain milk contains this natural sugar, which is digested slowly and has a low glycaemic index, meaning it does not cause rapid spikes in blood sugar.Added sugars in milk drinksFlavoured milk, chocolate milk, strawberry milk, café-style lattes, and milkshakes often contain large amounts of added sugar, which counts as “free sugar.” Consuming these drinks regularly can easily push someone over recommended daily sugar limits and cause sharp increases in blood glucose levels.Low GI of milk: According to a study published in University of Sydney, milk has a glycaemic index of around 46, meaning it releases glucose gradually into the bloodstream. This helps maintain stable blood sugar levels compared with high-GI foods such as white bread or sugary drinks.Insulin response: Milk protein can stimulate insulin release, sometimes more than expected for its carbohydrate content. This can help regulate blood glucose in some people, but those with insulin resistance should consider this effect when planning meals.Flavoured milk: Study published in ScienceDirect has shown that flavoured milk contains significantly more sugar than plain milk, which can lead to higher postprandial (after meal) blood glucose levels Sugary drinks: Regular consumption of sugary beverages can lead to rapid spikes in blood sugar and insulin levels, increasing the risk of developing type 2 diabetes over time1. General nutrition: Milk is nutrient-dense, providing protein, calcium, vitamin B12, iodine, and riboflavin. The natural sugars in plain milk offer energy while supporting bone, muscle, and nerve health. These natural sugars do not count toward daily free sugar limits, making plain milk a safe part of a balanced diet.2. Blood sugar and diabetes: People with diabetes or prediabetes should monitor their carbohydrate intake, including the lactose in milk. While it does affect blood sugar, the gradual release of glucose and the protein content help reduce spikes compared to sugary drinks. Plain milk is far healthier than sweetened beverages and can be safely included in a diabetes-friendly diet.3. Dental health: Lactose is less likely to cause tooth decay than sucrose, but frequent consumption of any sugar can contribute to cavities. Flavoured milk with added sugar poses a greater risk, particularly for children. Encouraging plain milk and maintaining oral hygiene is crucial.4. Children’s diets: Children benefit from the nutrients in milk. Plain milk should be a regular part of their diet, while flavoured or sweetened milk should be treated as an occasional indulgence to avoid exceeding safe sugar limits.According to NHS guidance, adults should consume no more than 30 g of free sugars per day. For children, the recommended limits are lower, depending on their age. Importantly, the natural lactose in plain milk does not count towards this daily limit. However, the added sugars in flavoured milks and milkshakes do count fully.Disclaimer: This article is for informational purposes only and does not constitute medical advice. Always consult a qualified healthcare professional before making any changes to your health routine or treatment.Also read | Dark chocolate helps control blood sugar; the perfect dessert swap