There's often a lot of talk about sugar in milk. Some recommend avoiding all types as much as possible, while others say natural sugars are OK, but it's the added sugars you have to watch out for. Wherever you stand on the spectrum of the sugar debate, it may be helpful to know that the sugar in milk, which is mainly lactose, is natural.
Of course, if you're opting for flavored milks, like chocolate milk or strawberry milk, they'll likely have added sugars in addition to the natural lactose, so keep that in mind when making your choices and read your labels carefully.
The sugar in milk, called lactose, is natural. However, chocolate or strawberry milk most likely has added sugar in it as well. Plain milk provides 12 grams of carbohydrates per cup in the form of natural sugars, while the carbohydrate content of chocolate milk shoots up to almost 29 grams due to sugar added during processing.
Natural vs. Added Sugars
You can divide the type of sugar in your diet into two major categories: natural sugar and added sugar. As the names imply, natural sugar is a class of sugar that's a natural component of foods. It hasn't been added by food manufacturers. On the other hand, added sugar is the type of sugar that's incorporated into foods during their manufacturing, processing and/or preparation.
Added sugar doesn't just refer to cane sugar itself. It also includes any sweeteners that are added during processing or preparation, like honey, maple syrup, brown rice syrup and high-fructose corn syrup. The sugar in milk, which is called lactose, falls into the category of natural sugars. That's because the milk naturally contains the lactose, which was added only by Mother Nature, herself.
What Is Lactose?
Lactose is a natural sugar and the major carbohydrate in all milk products. It's classified as a disaccharide, which means it's a complex sugar that's formed when two other simpler sugars (or monosaccharides) come together. Specifically, lactose is made up of molecules of the two simple sugars glucose and galactose.
In addition to lactose, milk also contains trace amounts of other natural sugars, like glucose, fructose, glucosamine and galactosamine.
The Carbs in Milk
All of the carbohydrates in milk come from its natural sugar content. Although most of the carbohydrates come from lactose, the other natural sugars contribute in small amounts to the total count as well.
One cup of plain, whole milk contains 12 grams of carbohydrates, while skim milk provides slightly more, or 13 grams per cup. Although milk is devoid of any dietary fiber, both skim and whole milk are a significant source of protein, providing 8 grams per cup.
Milk for Diabetics
Because milk is moderately high in natural sugar, it may seem logical that it's best to avoid milk for diabetics. However, the science doesn't totally agree.
A review published in Advances in Nutrition in May 2019 noted that the consumption of dairy products, like milk, is actually associated with a lower risk of Type 2 diabetes. Another review published in the same journal, Advances in Nutrition, in May 2018 agreed with these findings, adding that in addition to contributing to a reduced risk of metabolic syndrome and diabetes, dairy products may even slightly reduce the risk of developing heart disease.
Sweetened and Flavored Milks
However, these findings referred to plain milk and yogurt and don't apply to sweetened and flavored milks, like chocolate milk and strawberry milk. Unlike plain milk which only has natural sugar, flavored milks have added sugars, in addition to other added, and sometimes artificial, ingredients.
One cup of chocolate milk provides 29 grams of carbohydrates, all from sugar. If you do the math and subtract the 12 grams of natural sugar, that leaves 17 grams of added sugar, which is more than two-thirds the amount of added sugar the American Heart Association recommends that women have and almost half of the recommendation for men for an entire day.
Problems Digesting Lactose
But it's not just the carbohydrate count that's a problem for some people. Because the milk sugar lactose is made up of two other simple sugars, it must be broken down before your body can properly digest it. Your body uses a specialized enzyme called lactase, which is made in your small intestine, to do this.
Some people have trouble digesting lactose due to a condition called lactose intolerance. In those with lactose intolerance, the small intestine doesn't make enough lactase and, as a result, lactose moves through the system without being properly digested. These can cause uncomfortable symptoms like:
- Abdominal cramps and pain
If you're lactose intolerant, it's best for you to completely avoid lactose, even though it's a natural sugar. If you're not, natural sugars are OK in moderation, but it's the added sugars you should watch out for. Too much added sugar has been linked to weight gain, diabetes, heart disease and cavities.
Read more: 15 Reasons to Kick Sugar
Avoiding Added Sugars
Although nutrition advice is often conflicting, one thing that many experts agree on is that you should avoid added sugars as much as possible. Unfortunately, food manufacturers don't always make it easy for you to spot added sugars on nutrition labels. Sometimes added sugar is simply listed in the ingredient list as "sugar," but more often than not, it falls under a different name. Different names for added sugar include:
- High-fructose corn syrup (or just corn syrup)
- Brown sugar
- Brown rice syrup
- Fruit juice concentrate
- Anything that ends in -ose (dextrose, fructose, glucose, lactose, maltose, sucrose)
If you see any of these names on an ingredient list, you know there's added sugar in the food or drink and it's best to limit it or avoid it completely, especially if you're trying to control your blood sugar.
- Dairy Chemistry and Biochemistry: "Lactose"
- USDA National Nutrient Database: "Full Report (All Nutrients): Skim Milk"
- USDA National Nutrient Database: "Full Report (All Nutrients): Whole Milk"
- USDA National Nutrient Database: "Full Report (All Nutrients): Chocolate Milk"
- American Heart Association: "Sugar 101"
- University of Illinois Animal Sciences: "Milk Composition: Lactose"
- Advances in Nutrition: "Effects of Milk and Dairy Product Consumption on Type 2 Diabetes: Overview of Systematic Reviews and Meta-Analyses"
- Advances in Nutrition: "Introduction and Executive Summary of the Supplement, Role of Milk and Dairy Products in Health and Prevention of Noncommunicable Chronic Diseases: A Series of Systematic Reviews"
- John Hopkins Medicine: "Lactose Intolerance"
- Harvard Health Publishing: "Eating Too Much Added Sugar Increases the Risk of Dying With Heart Disease"