Milk and oat milk: what a glass of each actually gives you

In a network meta-analysis of 14 trials in 543 people, 17 fl oz (500 mL) of oat drink in place of cow's milk may lower total cholesterol by 4.6 mg/dL (0.12 mmol/L) (95% CI 0.01 to 0.24 lower), at very low certainty since few oat trials sit in the network. In a small open-label pilot, 32 healthy Norwegian women aged 18 to 40 who drank 20 fl oz (600 mL) of oat drink a day instead of semi-skim milk for 4 weeks saw LDL cholesterol fall by 15 mg/dL (95% CI 7.7 to 23; metric: 0.4 mmol/L, 0.2 to 0.6) against the milk group. The plainer difference is what sits in the glass. Cow's milk has about four times the protein, 3.27 g against 0.80 g per 3.5 oz (100 g) in USDA samples. Oat milk calcium averaged 148.5 mg per 3.5 oz (100 g) but ran from 48 to 300 mg depending on whether and how much a brand fortifies, while whole milk stayed between 116 and 130 mg.

How much is actually in it

• The 2025-2030 US Dietary Guidelines say the naturally occurring sugars in plain milk are not added sugars. — United States general population, Dietary Guidelines for Americans 2025-2030 Evidence E source
  Sugars of plain milk not counted as added sugars
• Unsweetened oat milk averages 148.5 mg calcium per 3.5 oz (100 g) but samples ran from 48 to 300 mg, while whole cow's milk stayed between 116 and 130 mg. — USDA Foundation Foods: Oat milk, unsweetened, plain, refrigerated (16 calcium samples) and Milk, whole, 3.25% milkfat, with added vitamin D (11 samples) (n = 16 and 11 samples) Evidence E source
  Oat milk calcium 148.5 mg per 3.5 oz (100 g), range 48 to 300, spread 170%; whole milk 123 mg, range 116 to 130, spread 11%
• Cow's milk carries about four times the protein of unsweetened oat milk, 3.27 g against 0.80 g per 3.5 oz (100 g) in USDA samples. — USDA Foundation Foods: Oat milk, unsweetened, plain, refrigerated and Milk, whole, 3.25% milkfat, with added vitamin D (n = Foundation sample sets) Evidence E source
  Oat milk protein 0.80 g per 3.5 oz (100 g), range 0.375 to 1.19; whole milk 3.27 g, range 2.93 to 3.51
• Unsweetened oat milk samples averaged vitamin D2 and vitamin B12 levels close to cow's milk, but some samples had none of either. — USDA Foundation Foods: Oat milk, unsweetened, plain, refrigerated (13-14 samples) and Milk, whole, 3.25% milkfat, with added vitamin D (12-24 samples) (n = 13 to 24 samples) Evidence E source
  Oat milk vitamin D2 1.69 micrograms per 3.5 oz (100 g) (0 to 2.64), B12 0.51 (0 to 0.89); whole milk vitamin D3 0.96 (0 to 1.38), B12 0.54 (0.46 to 0.59)

What a real portion looks like

• The 2025-2030 US Dietary Guidelines set a dairy goal of 3 servings a day for a 2,000-calorie diet, adjusted to individual calorie needs. — United States general population, Dietary Guidelines for Americans 2025-2030 Evidence E source
  3 servings of dairy per day at 2,000 calories
• The US survey food database sets a cup of oat milk and a cup of whole milk at the same 244 g. — FNDDS food codes 11360200 Oat milk and 11111000 Milk, whole (n = 2 foods) Evidence E source
  1 cup 244 g for both; quantity not specified 244 g for both

What cooking and storage change

• By USDA retention factors for dairy, heating milk for about 10 minutes keeps all its calcium and riboflavin but loses about 20% of vitamin B12 and 15% of folate. — USDA R6 retention factor for Dairy and Egg Products, milk heated approx. 10 min (code 2151) Evidence E source
  Retained: B12 80%, vitamin C 85%, folate 85%, thiamin 90%, B6 90%, calcium 100%, riboflavin 100%

What it does to your health

• The 2025-2030 US Dietary Guidelines recommend including full-fat dairy with no added sugars, while keeping saturated fat at no more than 10% of daily calories. — United States general population, Dietary Guidelines for Americans 2025-2030 Evidence E source
  Full-fat dairy recommended; saturated fat cap ≤10% of calories kept
• In a 4-week trial of 32 young women, drinking 20 fl oz (600 mL) of oat drink a day instead of cow's milk lowered LDL cholesterol by 15 mg/dL (0.4 mmol/L). — healthy women aged 18-40 who habitually drank cow's milk, Norway, 4 weeks, 20 fl oz (600 mL) a day (n = 32) Evidence B source
  LDL cholesterol -15 mg/dL (95% CI -23 to -7.7; metric: -0.4 mmol/L, -0.6 to -0.2); total cholesterol -12 mg/dL (95% CI -23 to 0; metric: -0.3 mmol/L, -0.6 to 0.0); HDL and triglycerides unchanged
• A network meta-analysis of 14 trials found oat drink may lower total cholesterol by only 4.6 mg/dL (0.12 mmol/L) compared with cow's milk, with very low certainty. — 14 randomized trials, 543 participants, at least 3 weeks, comparing soy, rice and oat drinks and cow's milk (n = 543) Evidence A source
  Oat drink vs cow milk total cholesterol -4.6 mg/dL (95% CI -9.3 to -0.39; metric: -0.12 mmol/L, -0.24 to -0.01), very low certainty; soy drink vs cow milk LDL -18 mg/dL (-33 to -3.9; metric: -0.47 mmol/L, -0.85 to -0.10), low certainty
• The 2025-2030 Dietary Guidelines for Americans, released in January 2026, call dairy an excellent source of protein, healthy fats, vitamins and minerals and recommend including full-fat dairy in a healthy diet. — United States general population, Dietary Guidelines for Americans 2025-2030 Evidence E source
  Federal position shifted to include full-fat dairy, as restated in a USDA final rule of 8 May 2026

Safety, limits and interactions

• The 2025-2030 US Dietary Guidelines advise stopping infant formula at 12 months and giving whole milk. — infants fed formula, Dietary Guidelines for Americans 2025-2030 Evidence E source
  Switch from infant formula to whole milk at 12 months
• Across 6 studies of children, drinking plant-based milk instead of cow's milk was linked to lower BMI, height and blood vitamin D. — children aged 1-18, 3 cross-sectional studies, 1 cohort and 2 clinical trials (n = 15815) Evidence C source
  Lower BMI, height and serum vitamin D with plant-based milk in observational studies; minimal effects in low-quality trials

What people believe that the data does not support

• The EU refused the claim that cow's milk supports dental health and healthy tooth development. — EU Register on nutrition and health claims, claim POL-HC-6549 Evidence E source
  Non-authorized
• The EU authorized the claim that oat beta-glucan lowers blood cholesterol. — EU Register on nutrition and health claims, claim POL-HC-6248 Evidence E source
  Authorized

Who this works differently for

• Under a US law enacted in January 2026, schools may offer whole and reduced-fat milk at lunch alongside low-fat and fat-free milk. — children in the US National School Lunch Program Evidence E source
  Whole and 2% milk allowed at school lunch in addition to 1% and fat-free, Whole Milk for Healthy Kids Act of 2025 (Pub. L. 119-69), enacted 14 January 2026; USDA rule effective 8 June 2026

What is still unknown

• The 2025 US Dietary Guidelines committee review found too little separate evidence on milk alternatives and called for trials that study them on their own. — USDA Nutrition Evidence Systematic Review, dairy milk and milk alternatives and growth, body composition and obesity Evidence E source
  Research gap stated

The bottom line

The label tells you more than the category does. Oat milk averaged 1.69 micrograms of vitamin D2 and 0.51 micrograms of B12 per 3.5 oz (100 g), close to whole milk on B12 at 0.54, yet some oat samples had none of either because they were unfortified. That matters most for vegans who count on oat milk for B12. A cup of either drink is 244 g in the US survey database, so the per-cup gaps are the per-100 g gaps times 2.44. Heating cow's milk for about 10 minutes keeps all of its calcium and riboflavin and loses about 20% of vitamin B12 and 15% of folate. That is a USDA group factor from 1975, not measured on any specific milk, and no such factor exists for oat milk. Two label claims come up. The EU refused the claim that cow's milk supports dental health. That means the evidence did not reach the bar at assessment, and it says nothing about milk harming teeth. The EU did authorize the claim that oat beta-glucan lowers blood cholesterol. The claim needs a minimum beta-glucan dose, and this page has no measure of how much beta-glucan an oat drink carries, so the claim does not carry over to a glass of oat drink by itself. The 2025 to 2030 Dietary Guidelines for Americans, released in January 2026, recommend including full-fat dairy with no added sugars. The same document keeps saturated fat at no more than 10 percent of daily calories, so full-fat milk has to fit inside that limit. It sets a goal of 3 dairy servings a day on a 2,000-calorie diet and does not say how big a serving of milk is. That is a position, with no evidence review of its own on dairy fat, and it says nothing about oat or other plant drinks. The guidelines also do not count the sugar naturally present in plain milk as added sugar, which does not extend to oat drinks with sugar added. For children the evidence is weak, and its signals are unfavorable to plant milk. Across 6 studies with 15,815 children aged 1 to 18, observational data linked plant-based milk in place of cow's milk to lower BMI, height and blood vitamin D, in studies that were mostly cross-sectional and did not separate oat milk from other plant milks. The low-quality trials in the same review showed minimal effects. The committee behind the 2025 US Dietary Guidelines found too little evidence on milk alternatives studied on their own and called for trials that test them separately. For babies fed formula, the guidelines say to stop formula at 12 months and give whole milk, and they say nothing about plant drinks for toddlers. Since a law enacted in January 2026, US schools may offer whole and 2 percent milk at lunch alongside 1 percent and fat-free. The law changes what schools may serve, makes no health finding and does not cover plant drinks. We have no card on allergy, intolerance or drug interactions for either drink, and none on giving either drink to babies under 1 year.

Sources

1. mkom-dga-04 · government guidance
   Some foods and drinks, such as fruits and plain milk, have naturally occurring sugars. The sugars in these foods are not considered added sugars.
   U.S. Department of Health and Human Services and U.S. Department of Agriculture, Dietary Guidelines for Americans, 2025–2030 (January 2026), p. 4 · checked 2026-09-29
2. mkom-r1-01 · USDA FoodData Central Foundation Foods, dataset
   Oat milk, unsweetened, plain, refrigerated: Calcium, Ca 148.5 MG, range 48.0-300.0 (median 146.3), 16 samples, spread 170%; Milk, whole, 3.25% milkfat, with added vitamin D: Calcium, Ca 123.0 MG, range 116.0-130.0 (median 122.0), 11 samples, spread 11%
   USDA FoodData Central, Foundation Foods, release 2026-04-30 · checked 2026-09-28
3. mkom-r1-02 · USDA FoodData Central Foundation Foods, dataset
   Oat milk, unsweetened, plain, refrigerated: Protein 0.796875 G, range 0.375-1.1875 (median 0.84375), spread 102%; Milk, whole, 3.25% milkfat, with added vitamin D: Protein 3.27 G, range 2.93-3.51 (median 3.25), spread 18%
   USDA FoodData Central, Foundation Foods, release 2026-04-30 · checked 2026-09-28
4. mkom-r1-03 · USDA FoodData Central Foundation Foods, dataset
   Oat milk, unsweetened, plain, refrigerated: Vitamin D2 1.694 UG, range 0.0-2.64, 13 samples; Vitamin B-12 0.5064 UG, range 0.0-0.89, 14 samples. Milk, whole, 3.25% milkfat, with added vitamin D: Vitamin D3 0.96 UG, range 0.0-1.38, 24 samples; Vitamin B-12 0.54 UG, range 0.46-0.59, 12 samples
   USDA FoodData Central, Foundation Foods, release 2026-04-30 · checked 2026-09-28
5. mkom-dga-02 · government guidance
   Dairy serving goals: 3 servings per day as part of a 2,000-calorie dietary pattern, adjusting as needed based on your individual caloric requirements.
   U.S. Department of Health and Human Services and U.S. Department of Agriculture, Dietary Guidelines for Americans, 2025–2030 (January 2026), p. 2 · checked 2026-09-29
6. mkom-r1-04 · USDA FNDDS 2021-2023, dataset
   Oat milk (FNDDS 11360200, FDC 2705412): 1 cup 244 g; Quantity not specified 244 g. Milk, whole (FNDDS 11111000, FDC 2705385): 1 cup 244 g; Quantity not specified 244 g
   USDA FNDDS 2021-2023, food codes 11360200 and 11111000 · checked 2026-09-28
7. mkom-r1-05 · USDA Nutrient Retention Factors Release 6, dataset
   USDA-RETN-R6:2151 MILK,HEATED APPROX 10MIN (Dairy and Egg Products): vitamin_b12 80%; vitamin_c 85%; folate_total 85%; thiamin 90%; vitamin_b6 90%; choline 90%; calcium 100%; riboflavin 100%
   USDA Table of Nutrient Retention Factors, Release 6 (2007), code 2151 · checked 2026-09-28
8. mkom-dga-01 · government guidance
   When consuming dairy, include full-fat dairy with no added sugars. Dairy is an excellent source of protein, healthy fats, vitamins, and minerals. ... In general, saturated fat consumption should not exceed 10% of total daily calories.
   U.S. Department of Health and Human Services and U.S. Department of Agriculture, Dietary Guidelines for Americans, 2025–2030 (January 2026), p. 2–3 · checked 2026-09-29
9. mkom-r1-06 · randomized controlled trial
   Over the four weeks, the oat drink group experienced a significant reduction in mean total cholesterol (-0.3 mmol/L (95% CI 0.6 to 0.0; p = 0.026) and LDL-cholesterol (–0.4 mmol/L (95% CI − 0.6 to − 0. 2; p = 0.002), compared to the cow’ s milk control group.
   Nutr J, 2026 · checked 2026-09-28
10. mkom-r1-07 · systematic review and network meta-analysis
    Substituting 500 mL of oat drink for either rice drink or cow milk may reduce total cholesterol, but the evidence is very uncertain [MD: –0.23 mmol/L (95% CI: –0.40, –0.05 mmol/L), MD: –0.12 mmol/L (95% CI: –0.24, –0.01 mmol/L), very low certainty, Supplemental Figure 9 and Supplemental Tables 13 and 14].
    Adv Nutr, 2026 · checked 2026-09-28
11. mkom-wf4-01 · government guidance
    On January 7, 2026, the U.S. Department of Health and Human Services and U.S. Department of Agriculture (USDA) jointly released the Dietary Guidelines for Americans, 2025-2030 ... The Dietary Guidelines state that “dairy is an excellent source of protein, healthy fats, vitamins, and minerals” and recommends including full-fat dairy as a part of a healthy diet.
    USDA Food and Nutrition Service, Expanding Fluid Milk Options in Child Nutrition Programs, final rule, Federal Register 2026-05-08, FR Doc 2026-09212 · checked 2026-09-29
12. mkom-dga-03 · government guidance
    If feeding or supplementing your baby with infant formula, stop feeding your baby infant formula at 12 months of age and give them whole milk.
    U.S. Department of Health and Human Services and U.S. Department of Agriculture, Dietary Guidelines for Americans, 2025–2030 (January 2026), p. 6 · checked 2026-09-29
13. mkom-r1-08 · systematic review
    Observational studies found that consumption of plant-based milk was associated with lower childhood body mass index (BMI), height, and serum vitamin D concentrations compared with cow milk.
    J Nutr, 2024 · checked 2026-09-28
14. mkom-r1-09 · EU claim register entry
    POL-HC-6549 (Cow’s) Milk And dairy products for which milk is the principle ingredient and no sugar has been added – e.g. yogurt, cheese. (Cow’s) Milk products help support dental health. (Cow’s) Milk helps support the normal and healthy development of teeth. (Cow’s) Milk contributes to dental health. Non-authorised
    EU Register on nutrition and health claims, claim POL-HC-6549, snapshot 2026-09-21 · checked 2026-09-28
15. mkom-r1-10 · EU claim register entry
    POL-HC-6248 Oat beta-glucan Oat beta-glucan has been shown to lower/reduce blood cholesterol. High cholesterol is a risk factor in the development of coronary heart disease -/- Authorised
    EU Register on nutrition and health claims, claim POL-HC-6248, snapshot 2026-09-21 · checked 2026-09-28
16. mkom-wf4-02 · government guidance
    The WMFHKA specifically allows schools to offer whole and reduced-fat (2 percent) milk in addition to low-fat (1 percent) and fat-free options at school lunch.
    USDA Food and Nutrition Service, Expanding Fluid Milk Options in Child Nutrition Programs, final rule, Federal Register 2026-05-08, FR Doc 2026-09212 · checked 2026-09-29
17. mkom-r1-11 · USDA NESR research recommendation, 2024
    Conduct longitudinal studies, particularly RCTS, examining milk alternatives independently.
    USDA NESR 2024, Dairy Milk and Milk Alternatives and Growth, Body Composition, and Risk of Obesity · checked 2026-09-28