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If you’ve ever examined the nutrition label on a carton of milk, you’ve probably noticed that most kinds of milk contain sugar.

The sugar in milk isn’t necessarily bad for you, but it’s important to understand where it comes from — and how much is too much — so that you can choose the best milk for your health.

This article explains milk’s sugar content and how to identify products with too much sugar.

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Why is there sugar in milk?

Many people try to avoid added sugar — and for good reason.

Foods high in added sugar contribute extra calories to your diet without providing any additional nutrients. They’re also linked to weight gain and metabolic syndrome, a condition that increases your risk of diabetes and heart disease (1, 2).

However, some foods contain naturally occurring sugars.

That’s why some products, such as dairy and nondairy milks, show sugar content on their nutrition panel even if sugar isn’t included as an ingredient.

These natural sugars are the main carbohydrate in milk and give it a lightly sweet taste — even when drunk plain.

In cow’s milk and human breast milk, the sugar comes primarily from lactose, also known as milk sugar. Nondairy milks, including oat, coconut, rice, and soy milk, contain other simple sugars, such as fructose (fruit sugar), galactose, glucose, sucrose, or maltose.

However, keep in mind that sweetened versions, including chocolate milk and flavored nondairy milks, harbor added sugar as well.

Most dairy and nondairy milks contain naturally occurring sugars like lactose. Sweetened versions provide added sugar, too.

Sugar content in various types of milk

Milk’s sugar content varies significantly depending on the source and how it’s made — as some products have sugar added.

Here are the sugar levels in 1 cup (240 ml) of various types of milk (3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14):

• Human breast milk: 17 grams
• Cow’s milk (whole, 2%, and skim): 12 grams
• Unsweetened rice milk: 13 grams
• Chocolate cow’s milk (skim): 23 grams (sugar added)
• Unsweetened vanilla soy milk: 9 grams
• Chocolate soy milk: 19 grams (sugar added)
• Unsweetened oat milk: 5 grams
• Unsweetened coconut milk: 3 grams
• Sweetened coconut milk: 6 grams (sugar added)
• Unsweetened almond milk: 0 grams
• Vanilla almond milk: 15 grams (sugar added)

Among the unsweetened nondairy varieties, rice milk packs the most sugar — 13 grams — while almond milk contains none at all. Cow’s milk is comparable to rice milk at 12 grams.

In general, sweetened types have far more sugar than unsweetened ones. Chocolate milk delivers a whopping 23 grams in just 1 cup (240 ml).

The U.S. Department of Agriculture (USDA) recommends limiting added sugar to under 10% of your total daily calorie intake — or about 12.5 teaspoons (50 grams) on a 2,000-calorie diet (15).

You might exceed that limit with sweetened milk alone if you drink more than one glass each day.

Milk’s sugar content varies greatly depending on its source and whether it contains added sugar. Among the unsweetened nondairy varieties, rice milk has the most sugar and almond milk the least. Cow’s milk has slightly less than rice milk.

The health effects of sugar in milk

The simple sugars in all types of milk have several effects on your health. They’re quickly digested and broken down into glucose, the major source of energy for your body and an essential energy source for your brain (16).

The lactose in dairy and breast milk is broken down into galactose as well as glucose. Galactose is especially important for central nervous system development in infants and young children (16, 17).

If not fully digested, lactose functions like prebiotic fiber, which feeds the healthy bacteria in your gut. Undigested lactose also helps improve your body’s absorption of certain minerals, such as calcium and magnesium (17).

Glycemic index and milk

Because all types of milk contain carbs, they can be measured on the glycemic index (GI), a scale of 0–100 that denotes to what extent a food affects blood sugar. Lower GI foods raise blood sugar levels more slowly than higher GI ones.

Fructose, which is found in coconut milk and several nut milks, has a low GI and may be preferable if you’re watching your blood sugar levels or have diabetes (18, 19).

A review of 18 studies in 209 people with diabetes found that when fructose was used to replace other carbs, average blood sugar levels dropped by 0.53% over 3 months (18).

However, fructose may raise your triglyceride levels and trigger digestive issues like gas and bloating in some individuals (18).

Lactose, the sugar in cow’s milk, likely less significantly affects blood sugar than other forms of sugar. Yet, the glucose and maltose in rice milk have a high GI, meaning that they’re quickly digested and may raise your blood sugar levels significantly (19).

If you’re watching your blood sugar, the best choice may be unsweetened almond milk, as it has little to no sugar.

The natural sugars in milk fuel your body and brain, but some affect your blood sugar more than others. The lactose in breast and dairy milk is especially beneficial for infants and young children.

How to avoid milk with added sugar

Whether you choose dairy or nondairy milk, you should aim for unsweetened varieties to minimize your intake of added sugar.

In the United States, the Food and Drug Administration (FDA) is redesigning food labels to explicitly call out the grams of added sugar — making it easier to identify which milks to buy or avoid (20).

This rule will go into effect in January 2020 for large food manufacturers and January 2021 for smaller companies (20).

Outside of the United States, nutrition labels may vary in detail and should be read carefully. If you see any form of sugar on the ingredient list, that means it’s added.

Common names for added sugar include:

• corn syrup or high-fructose corn syrup
• brown rice syrup
• agave nectar
• coconut sugar
• barley malt
• malt syrup
• maltose
• fructose

You can also look for the word “unsweetened” on the label.

It’s best to choose unsweetened milk and avoid those with added sugar. You should always check the ingredient list for words that indicate added sugar.

The bottom line

All forms of milk contain sugar, but there’s no reason to avoid the natural, simple sugars in unsweetened milk.

Unsweetened milk is an excellent source of carbohydrates, which help fuel your brain and body and may even offer additional benefits.

Nonetheless, you should always avoid milk with added sugar due to negative health effects.