Get out my hay: Which kind of milk should you drink and why?
Soy Milk vs. Almond Milk vs. Goat Milk vs. Rice Milk vs. Regular Cow Milk
Too Much Information on Milk and Milk Alternatives
Once upon a time, “milk” for most North Americans meant full-fat cow’s milk, and that was that. Eventually, that era ended with the rise of low-fat milk, and so began the era of full-fat, low-fat and fat-free cow’s milk. I was born during that time.
Now that era, too, has passed. “Milk” can mean a lot of things these days— several types of cow milk, goat milk, or any of a number of vegan alternatives — including soy, rice, coconut, and almond milk. And that’s before we even get into the question of organic vs. non-organic.
Now, milk is perhaps second only to eggs as one of the most controversial foods. Perhaps no other food is both so beloved and so reviled. In this article I’ll set out to answer the question: if you drink milk, which type of milk should you be drinking?
A Comparison of the Different Types of “Milk”
Believe it or not, the research suggests good old-fashioned cow milk is actually very healthy. One assessment found that milk consumption was associated with greater muscle mass, lower risk of type 2 diabetes, childhood obesity, stroke and cardiovascular disease, and greater bone density.
Another meta-analysis found that milk consumption is not associated at all with all-cause mortality, meaning it’s probably neutral for your health overall. However, this study was only controlled for total calorie intake and level of exercise, not for dietary intake of other specific foods, like sweetened vs non-sweetened breakfast cereals. This raises the possibility that milk may be positive for your health as long as you’re not eating Cocoa Puffs with it.
There is a downside to cow milk: many people have trouble digesting it. You can take pills containing lactase—the enzyme that digests lactose—or you can drink milk fortified with lactase. That should work just fine if you’re lactose-intolerant, but lactose isn’t always the issue.
One-tenth of people are also allergic to casein, one of the two main proteins in milk. Dairy consumption is also associated with an increased risk of acne, and casein again seems to be the likely culprit here. To complicate things, there is some emerging evidence that issues like acne are caused not by casein, but by bits of free-floating beef RNA in milk that are absorbed into the bloodstream, causing an autoimmune response.
In any case, if you suffer from acne or have an allergic reaction to even lactase-fortified milk, you should at least experiment with cutting out cow’s milk.
As a final note, the consumption of non-cow milk is associated with lower height in children. However, this study did not differentiate between different milk substitutes, nor did it identify a mechanism behind the association. That means we don’t know whether the association is due to ingredients in some milk substitutes, or merely the higher protein content of cow milk.
Whole milk, reduced-fat or skim milk?
Higher milk fat consumption is associated with a lower risk of obesity in children. This doesn’t mean, however, that high milk fat consumption prevents obesity; it could well be that parents of obese children are more likely to feed their kids skim milk — and that this simply doesn’t work to prevent obesity. At the very least, drinking full-fat milk doesn’t cause obesity.
Fat is an important part of a balanced diet. Meals that contain at least a few grams of fat make you feel fuller for longer than fat-free meals, although more fat isn’t necessarily better beyond a certain point. Also, one study suggests that the amino acids in whole milk are more easily absorbed than those in skim milk.
Furthermore, consuming whole milk or a whey-casein blend produces more sustained muscle protein synthesis than consuming either skim milk or whey protein in isolation. In other words, whole milk helps you build more muscle than skim milk, which indirectly prevents fat gain and even burns fat by raising your metabolism.
That study notably only compared whole and skim milk, but not reduced-fat milk, raising the possibility that reduced-fat milk may offer similar amino acid bioavailability to full-fat milk.
Based on that study as well as the satiating effects of including fat in meals, milk should have at least some fat, but there’s no clear winner between whole and low-fat milk. People who are trying to lose weight should probably opt for reduced-fat milk, while those who are trying to gain weight should favor whole milk. Those who are maintaining their current weight can just pick whichever they prefer.
So that covers fat levels for cow’s milk. Now how does it compare to other types of milk altogether?
Nutritionally, goat milk is similar to cow milk, but with higher protein content. While it’s widely seen as less allergenic, the evidence for that is debatable—it contains less casein than cow’s milk, but has similar amounts of lactose, and is highly similar overall. And while having less casein is good from an allergenic standpoint, it’s bad from a protein-synthesis standpoint.
One experiment using 58 subjects found that 25% of people who are allergic to cow milk are also allergic to goat milk. Another study with 12 subjects found that number to be 75%, but added that “for the 25 % of patients that tolerate goat’s protein, goat’s milk can be an excellent substitute in children older than 2 years old.”
Studies have usually found no difference between babies being fed goat milk vs. cow milk, although researchers in one study noted that the protein content of goat milk is more similar to human breast milk than cow milk. Another study said that unmodified goat milk should not be favored over cow milk for feeding babies due to the higher protein and lower folate (vitamin B9) content. The study also noted that goat milk is not less allergenic than cow’s milk overall.
If you’re allergic to cow milk, goat milk is worth a try, although if it is not locally available you may need to buy it online in powdered form. Babies under 2 years old who are allergic to cow milk should not be given goat milk products without consulting a doctor, as they may or may not also be allergic to goat milk.
Almond milk lacks both casein and lactose, and almost everyone can digest it just fine—though it is not a viable choice if you have an allergy to tree nuts. In lab tests, infants who were allergic to cow milk were shown to have no adverse reaction to almond milk.
While it’s great from an allergy standpoint, almond milk does not have a complete amino acid profile — the protein in it isn’t as healthy as that in animal milk, and it has less protein overall. It also often has added sugar; if you choose to drink it, get a sugar-free brand, and consider adding a natural sweetener such as stevia if you want it to be sweeter.
If you’re considering non-dairy milk because of concerns about the environment, you should note that almonds use a tremendous amount of water to grow, contributing to water shortages, loss of groundwater, and increased water costs, as well as indirectly to the environmental impact of reservoirs and other water infrastructure. The same charges can be leveled against most animal products, but not against other vegan milk substitutes.
Unlike most plant protein sources, soy has a complete amino acid profile, and soy milk has decently high protein content. Studies have sometimes found soy protein to produce greater muscle protein synthesis than milk protein isolate; however, it consistently performs worse than whole milk in this regard.
Unlike almond milk, soy milk is not a clear alternative if you have an allergy to cow milk. In the same study referenced in the previous section, 23% of cow milk-allergic infants showed sensitivities to soy milk.
Since soy contains few of the same potential allergens as milk, this also suggests that the allergies are at least partly caused by digestive issues in the patient, like leaky gut syndrome, rather than any inherent toxicity of the milks themselves.
Soy also contains phytoestrogens that mimic the effect of natural estrogen, causing hormonal disruptions. While this isn’t a cause to completely avoid soy, it should be consumed in moderation, particularly during puberty.
Commonly used as a cooking ingredient, coconut milk is more rarely consumed as a milk substitute. Coconut milk is naturally lower in protein and higher in fat than any other form of milk, although coconut milk meant for drinking is always reduced in fat.
Due to its inferior protein content with a poor mix of amino acids, coconut milk by itself is not an adequate milk substitute. On the plus side, coconut allergy is rare and is not associated with nut allergies.
Coconut oil is very rich in saturated fat, which isn’t the best thing for cardiovascular health. It also contains a high proportion of medium-chain fatty acids. There is some evidence to suggest that these fatty acids can slightly boost your metabolic rate, and one controversial study even found that consuming coconut oil helped men to burn more belly fat.
These medium-chain fatty acids are particularly helpful to anyone on a ketogenic diet, as they are more ketogenic than other fats. That means that consuming sugar-free coconut milk or oil will allow you to eat more protein, or even somewhat more carbohydrates, while staying in ketosis — a considerable boon on that diet. (For more information on the ketogenic diet, read A Blueprint for Fat Loss with Slow Carb, Low Carb & Keto Diets.)
Rice milk is sometimes favored by patients who have severe allergic reactions to milk and other milk substitutes. Unfortunately, it has an unfavorable nutritional profile. Replacing milk with rice milk led to severe malnutrition in food allergy patients where it was attempted as part of an elimination diet to target food allergies. Rice does contain many nutrients like folic acid, magnesium and phosphorous, but it also contains the antinutrient phytic acid, which binds to many minerals and prevents their absorption. Ironically, consuming milk — as in regular cow milk — with rice enhances the absorption of zinc from the rice.
All in all, rice milk is a safe option if you have milk allergies and need a substitute, but it isn’t very nutritious. If you drink it, you’ll need to consume a multivitamin, or more meat and vegetables, or otherwise replace the nutrients you would have gotten from milk.
Should Milk Be Organic?
Eating organic is widely considered the healthy thing to do even by people who don’t actually do it. You may be surprised to learn, then, that the evidence for organic food as more nutritious is mixed, and overall not very strong at all.
Organic food does have somewhat fewer pesticide residues than non-organic food; however, the difference is too small to make a statistically significant difference in health outcomes, even when large populations are studied.
Organic food usually contains slightly more micronutrients — vitamins, minerals, and anti-oxidants — than conventionally-grown food. Once again, though, the difference is tiny and arguably insignificant.
When it comes to animal products, and to dairy, in particular, “organic” seems to have more of an advantage. Organic milk has a more favorable macronutrient composition — more protein and a healthier mix of fats — than non-organic milk. This is believed to be due to how organic cows are fed, rather than the absence of steroids, pesticides, or anything of that nature.
The majority of controlled human studies find no beneficial health effects of eating organic food. It must be noted however that short study durations and the limited contribution of the studied food to the overall diet — like a single glass of milk a day — greatly limit the scope and generalizability of these findings.
Overall, eating local is far more impactful than eating organic, because locally-sourced food will be fresher. Since many nutrients in food break down relatively quickly, freshness counts for a lot — far more than eating organic.
Animal products — and milk, in particular — may be an exception to this. Therefore, my conclusion is that animal milk products should be organic if you can afford them, but it’s not strictly necessary. Everything you eat, especially produce, would ideally be sourced locally. Unfortunately, milk and milk substitutes are hard to obtain from local sources due to economies of scale and refrigeration needs (hard to have a big fridge at a farmer’s market), but it’s something to consider nonetheless.
In addition to the nutritional impacts of eating organic foods, however, one could consider the environmental and health impacts on those producing the foods.
So Which Milk Is Best For You?
Looking at the research, we can determine that cow milk—either whole or reduced-fat and ideally also organic—still seems to be the best option from both health and fitness standpoints, provided you don’t suffer allergy issues from it. That’s a big caveat, as cow’s milk does have the highest allergenic potential.
Many people are lactose-intolerant, but that can generally be solved by drinking lactase-fortified milks like Lactaid. Unfortunately, at least ten percent of people are allergic to milk for other reasons besides lactose; there’s no cure for milk allergy except to not drink milk.
For those who have trouble with cow milk, goat milk is worth a try, although there’s a high chance you’ll be allergic to it too. There’s really no advantage to goat milk over cow milk, other than the chance that you might not be allergic to it.
For vegans, soy milk is the option that provides the best protein content. A mix of soy with another type of vegan milk might be even better since mixes of different proteins consistently produce more protein synthesis than one type of protein in isolation.
For those with milk allergies and not tree nut allergies, almond milk is your best bet, as it has a decent nutrient profile and almost no potential to cause an allergic reaction. However, soy and goat milks might also be okay for you, and if they are, they seem to be healthier than almond milk.
Overall, rice milk is the big loser here. Although it is hypoallergenic, almond milk is too — and has a better nutrient profile as well. There seems to be no advantage to it, other than being better for the environment than almond milk.
Coconut milk isn’t great for you, as it’s high on saturated fat and low on protein and nutrients. Unsweetened coconut oil is very useful for ketogenic dieters, both as a beverage and a cooking additive. Otherwise, it’s not any better nutritionally than rice milk.
The protein content of vegan milks can be improved by mixing in a little bit of whey or casein protein, or better yet, a whey-casein blend. There is an argument to be made for blending two types of milk—almond and rice, for instance, or soy and goat. This is because protein blends produce better muscle protein synthesis than protein isolates and because the body needs a variety of nutrients,
However, people with milk allergies probably shouldn’t try to blend two types of milk—other than maybe almond and rice—since it raises the chance that at least one component of the blend will be something they’re allergic to.
Those concerned with the environmental impact of their food should favor plant-based products, but not almonds. In other words, drink soy milk if you’re not allergic to it, but otherwise, opt for either rice or coconut milk, or a blend of the two.
Sometimes mind-blowing new information overturns the conventional wisdom. This isn’t really one of those times, except inasmuch as skim milk has turned out to be inferior to fatty milk.
The bottom line: most people can go ahead and enjoy a glass or two of milk a day. Maybe organic, maybe with added lactase. As long as you can digest it properly, cow’s milk (whole or reduced-fat) is great for you. To get the maximum benefit from it, you should make it part of a balanced diet — and lift some weights, since milk helps you build muscle.