Dairy vs. Plant-Based Milks: Which is the Healthiest Option?

By M. Javad Ershad, MD

Picture a Saturday morning at the grocery store. You’re facing a wall of various types of milk: dairy, soy, almond, oat, and even hemp milk. Each one has its own nutritional profile and health claims, so it’s easy to feel overwhelmed. How do you choose the healthiest option?

Let’s compare the major contenders – how they’re made, their nutrition, taste, and potential benefits and drawbacks – to assess which milk is best for you.

Dairy Milk

Dairy milk (or cow’s milk) is the traditional choice. How it’s made: Simply by milking cows (with pasteurization to ensure safety). Nutrition: One cup of 2 percent milk has roughly 8 grams of complete protein and about 300 mg of calcium, plus potassium, B vitamins, and often added vitamin D. These nutrients help build strong bones and muscles, and milk is one of the best dietary sources of calcium and vitamin D. Dairy milk contains about 12 grams of natural sugar (lactose) per cup and some saturated fat in whole milk. Taste: Creamy and mildly sweet, very versatile in drinks and recipes.

Pros:

• Nutrient-dense: Provides high-quality protein and many vitamins/minerals (calcium, vitamin D, B12, etc.) in each cup.
• Bone health: Excellent source of calcium and vitamin D to support bone strength as you age.
• Widely recommended: Included in dietary guidelines as part of a healthy diet (especially low-fat versions) due to its broad nutritional benefits.

Cons:

• Lactose: Contains lactose sugar, which many adults cannot fully digest, leading to gas or bloating if lactose intolerant.
• Saturated fat: Whole milk is high in saturated fat, which can raise LDL cholesterol; low-fat or skim is a better choice for heart health.
• Allergies/sensitivities: Not suitable for those with milk protein allergy or those avoiding animal products.

Soy Milk

Soy milk is a powerhouse among plant-based milks. How it’s made: By soaking and grinding soybeans with water, then filtering. Often fortified with calcium, vitamin D, and B12 to parallel dairy milk’s nutrients. Nutrition: One cup of unsweetened soy milk has roughly 7 – 8 grams of protein (comparable to dairy) and is naturally low in saturated fat. Fortified soy milk provides calcium and vitamin D in amounts similar to dairy milk. It also contains isoflavones (natural compounds in soy). Taste: Smooth and fairly creamy; a subtle bean flavor that’s usually mild (vanilla or other flavors can mask it).

Pros:

• High in protein: Soy milk offers almost as much protein as dairy milk. And unlike most plant-based proteins, soy protein is a complete protein, meaning that it contains all the essential amino acids.
• Nutrient-rich: Fortified soy milk has calcium, vitamin D, and vitamin B12 levels similar to dairy. It’s the only plant milk counted as part of the dairy food group in U.S. dietary guidelines.
• Heart-healthy and Safe: It is healthier than dairy milk in that there is no lactose or cholesterol, and it is very low in saturated fat. Regarding safety, studies show soy foods do not increase breast cancer risk or “feminize” men (no effect on male hormone levels). Also, soy intake does not disrupt thyroid function in people with adequate iodine.

Cons:

• Taste preference: Some people notice a bean-like aftertaste in soy milk that they don’t enjoy.
• Allergy: Soy is a common allergen, making soy milk unsuitable for some.
• Needs fortification: Unfortified soy milk lacks calcium and vitamin D, so be sure to choose fortified brands to get these nutrients.

Almond Milk

Almond milk is a very popular milk alternative made from almonds. How it’s made: By blending almonds with water and straining out the solids. (Commercial versions usually add vitamins and minerals and sometimes thickeners). Nutrition: Extremely low in calories (about 30 to 40 calories per cup) but also very low in protein (only 1 gram per cup). Almond milk is often fortified to provide roughly 300 mg of calcium and vitamin D, making it similar to dairy milk. It naturally has vitamin E from almonds. Taste: Light and slightly nutty; the texture is thinner compared to dairy milk.

Pros:

• Low calorie: Almond milk is a good option for those watching calories since it has significantly fewer calories than other milks.
• No lactose or saturated fat: Naturally lactose-free and contains almost no saturated fat.
• Fortified nutrients: Fortified almond milk can provide calcium and vitamin D comparable to dairy milk, which helps keep bones strong, especially for those on a dairy-free diet.

Cons:

• Very low protein: Only about 1 gram of protein per cup, so it doesn’t offer the satiety, muscle benefits, or high protein levels of dairy or soy milk.
• Nut allergen: Unsafe for those with nut allergies.
• Often sweetened: Many almond (and other nut) milks have added sugars, particularly in flavored versions. Therefore, be sure to choose unsweetened options to avoid extra sugar.

Oat Milk

Oat milk is a newer contender of milk options made from oats. How it’s made: By blending water with oats (often rolled oats), sometimes using enzymes to break down the oats, then straining. Nutrition: About 90 to 120 calories per cup, with 2 to 4 grams of protein (less than half the protein levels of dairy or soy). Oat milk contains higher amounts of carbohydrates (about 15 grams per cup) and roughly 2 grams of fiber (in the form of beta-glucans). Oat milk is usually fortified with calcium, vitamin D, and B12. Taste: Creamy and naturally sweet (the oat starch breaks down into sugars), with a smooth texture that foams well for lattes.

Pros:

• Contains fiber: With roughly 2 grams of fiber per cup, oat milk can help lower LDL (“bad”) cholesterol, which supports heart health. This benefit is unique to oat milk.
• Allergen-friendly: No dairy, soy, or nuts, so it’s a safe choice for those with multiple allergies or intolerances.
• Rich texture: Creamy texture and a mellow, sweet taste that many people enjoy as a dairy-milk substitute.

Cons:

• Low protein: Only about a third of the protein of dairy milk, so it’s not as filling or muscle-supportive. If you drink oat milk, you’ll need additional protein sources in your diet.
• Higher in carbs: Oat milk has the highest amount of carbohydrates. While much of the carbohydrates come from healthy whole grains, the higher amount could be a concern for those watching blood sugar or total carbohydrates in their diet (especially if the oat milk is sweetened).
• May contain added oil or sugar: Some brands of oat milk add oil for creaminess and sugar for taste, so be sure to look for unsweetened and low-oil options if you are monitoring your calories.

Hemp Milk

Hemp milk is made from hemp seeds. How it’s made: By blending hemp seeds with water and straining out solids. (Hemp seeds come from the hemp plant but have no THC, so they aren’t intoxicating.) Nutrition: Hemp milk contains about 60 to 80 calories per cup, with about 2 to 3 grams of protein. Hemp milk has 4 to 6 grams of fat per cup, mainly polyunsaturated fats like omega-3 and omega-6 fatty acids, and it is very low in carbohydrates (almost zero if unsweetened). Hemp milk is often fortified with calcium and vitamin D. Taste: A distinct earthy and nutty flavor with a slightly thin consistency. It’s not as sweet or creamy as oat or almond milk.

Pros:

• Healthy fats: Provides beneficial omega-3 and omega-6 fatty acids that support heart health, which is a plus that most other milks don’t have.
• Allergy-friendly: Hemp milk does not contain dairy, soy, or nuts, so it’s a good alternative for those who have those common allergens.
• Moderate nutrients: Usually fortified with calcium and vitamin D, it has a bit more protein than almond milk (though still far less than soy and dairy).

Cons:

• Low protein: Only about 2 to 3 grams of protein per cup, so it’s not as protein-rich as most other milks.
• Acquired taste: The earthy, seed-like flavor isn’t for everyone and might make it less appealing as a daily drink.
• Availability and Fortification: Hemp milk can be harder to find than other types of milk. Also, unfortified hemp milk offers much less calcium and B12 than dairy milk, so be sure to look for fortified versions.

Which Type of Milk is Best?

Each type of milk has its pros and cons, and given your specific health goals and taste preferences, you may select one type over the other.

But considering all the factors, I say that fortified soy milk comes out on top for most adults. Fortified soy milk is the closest to dairy in key nutrients and protein levels, and it’s the only plant milk endorsed as a true dairy equivalent in the U.S. dietary guidelines. Soy milk provides the high-quality protein, calcium, and vitamin D that adults (especially women over 45) need without the lactose or saturated fat found in dairy milk. Importantly, decades of research have shown that soy is safe and even offers health benefits.

Dairy milk is my second recommendation. It is very nutritious, so if you can tolerate the lactose, low-fat cow’s milk is also an excellent choice. But for those looking to go plant-based or lactose-free, soy milk is the most balanced, evidence-backed choice for overall health.

Almond, oat, and hemp milk can also fit into a healthy lifestyle – just be mindful of their nutritional gaps (like protein) and remember to choose fortified and unsweetened versions.