The milk section at the supermarket has become one of the most complex to navigate. Alongside classic whole cow's milk, skimmed, and semi-skimmed versions, you'll find organic varieties, lactose-free options, calcium-enriched, and high-digestibility formulas. Then there are the plant-based "milks": oat, almond, soy, rice, coconut, cashew, hemp. Each has a different nutritional profile, different environmental impact, and specific uses. There's no universally "best" choice—there's the right choice for your needs.

Conventional cow's milk: what it contains

Whole cow's milk is a complete food: high-quality proteins (casein and whey proteins, with all essential amino acids), highly bioavailable calcium (120 mg per 100 ml), vitamin D (naturally present in small amounts, often added), vitamin B12, iodine, potassium. The fats in whole milk are predominantly saturated (about 65% of total lipids), with small amounts of omega-3.

Conventional milk often comes from intensive farms where cows have no access to pasture and are fed mainly grain and soy-based feed. Antibiotic use is regulated (food residues: very low limits, monitored), and growth hormone use is banned in Europe (unlike the USA).

Organic milk: the real differences

Certified organic milk has two main differences from conventional milk. First: organic feeding of cows (feed without pesticides, GMOs, or preventive antibiotics). Second: mandatory access to pasture for at least 60% of their diet during the growing season. This second point has measurable nutritional consequences: organic milk contains on average 50% more omega-3 than conventional milk. Pasture is rich in omega-3 fatty acids, which transfer into the milk. For children and pregnant women, this difference is nutritionally significant.

Lactose-free milk: who really needs it

Lactose-free milk is regular cow's milk with the enzyme lactase added, which pre-digests lactose into glucose and galactose. Nutritionally, it's identical to regular milk: same proteins, same calcium, same vitamins. The only difference is a slightly sweeter taste (lactose, a mildly sweet sugar, is converted into sweeter sugars). For those with documented lactose intolerance, it's the solution that allows you to benefit from milk's proteins and calcium without symptoms. For those without intolerance, it offers no additional benefits and costs 15-30% more.

Plant-based "milks": the main alternatives

Soy milk: the closest to cow's milk in protein content (3.3-3.5g per 100ml, vs 3.5g in cow's milk). The only plant-based milk with complete proteins. Calcium and vitamin D are normally added (fortified). Recommended for those seeking protein equivalence in a vegan diet. Not for those with soy allergies.

Oat milk: the most popular in recent years. Rich in beta-glucans (soluble fiber that lowers cholesterol). Low protein content (1g per 100ml). Naturally sweet (starches are partially hydrolyzed into sugars during production). Environmental impact among the lowest of plant-based milks. Not for those with celiac disease (unless certified gluten-free).

Almond milk: the lowest calorie content (about 30-40 kcal per 100ml vs 65 for whole milk). Very little protein (0.5-1g). Calcium must be added because it's not naturally present in significant quantities. Good source of vitamin E if the beverage is made with a good percentage of almonds (check the label: some contain only 2-3% almonds). It's not a nutritionally equivalent substitute for cow's milk.

Rice milk: very digestible, sweet and neutral taste. Very little protein (0.1-0.3g). High glycemic index. Contains inorganic arsenic in amounts that would discourage frequent use as the sole milk for small children. Not the best among plant-based options for exclusive daily use.

How to choose based on your needs

For calcium and protein equivalent to cow's milk: organic cow's milk or soy milk fortified with calcium. For lactose intolerance: lactose-free organic milk or soy or oat milk. For children (over 1 year): cow's milk preferably organic; if using plant-based options, only soy milk fortified with calcium and vitamin D (others have too little calcium). For an adult vegan diet: rotation of soy and oat, both fortified. For those wanting to reduce environmental impact: oat and soy have the lowest carbon footprint among all milks.

How to read plant-based milk labels

First thing: check the percentage of the "milk" listed (e.g., "2% almonds"). If it's low, you're mainly buying water with additives. Look for at least 10% for nut milks. Then check if it's "fortified" with calcium (at least 120 mg per 100ml, equivalent to cow's milk), vitamin D, and vitamin B12 (essential for those following a vegan diet). Finally: added sugars. Many commercial plant-based milks add sugar or rice syrup. Always prefer the "unsweetened" version.

Is organic milk worth the extra cost?

It depends on the use. For growing children and pregnant and breastfeeding women: the 50% more omega-3 in organic milk is nutritionally significant. It's worth the extra cost. For healthy adults with a varied diet that includes fish and nuts: the omega-3 difference is less critical. You can choose organic for ethical reasons (better farming conditions) or financial reasons (if budget allows), but it's not essential for health if your diet is already rich in omega-3 from other sources.

Does milk help or not? The calcium question

Calcium in cow's milk has very high bioavailability (about 30-35% absorbed). Plant-based calcium sources have variable bioavailability: tofu with calcium sulfate about 31% (similar to milk), broccoli 49% (excellent), spinach 5% (very little due to oxalates that bind it), legumes 17-24%. Those eliminating milk from their diet can get sufficient calcium from: fortified plant-based milks, tofu, almonds, broccoli, cabbage, sardines with bones. But it requires conscious planning—it's not automatic.