Plant Milk vs Dairy: His & Hers?

When it comes to osteoporosis risk, common wisdom says “get plenty of dairy”. However, there are several things to bear in mind:

• Milk is a great source of calcium, which is useless to the body if you don’t also have good levels of vitamin D and magnesium.
• People’s vitamin D levels tend to directly correlate to the level of sun where they live, if supplementation isn’t undertaken.
• Plant-based milks are usually fortified with vitamin D (and calcium), by the way.
• Most people are deficient in magnesium, because green leafy things don’t form as big a part of most people’s diets as they should.

See also: An update on magnesium and bone health

And of course, dairy has its own health risks, the relatively most well-known of which (sadly still not that well-known) is inflammation; see: How to Prevent (or Reduce) Inflammation

His & Hers

It’s interesting that some of the other health benefits/risks of dairy are contentious (i.e. mixed evidence), because in vitro modelling of sex differences in digestion of different kinds of milk (plant and animal) have found:

❝In the case of dairy milk, male gut conditions liberated various known bioactive peptides with antimicrobial, Dipeptidyl peptidase-4 inhibitor and cholesterol regulating activities.

Contrary, female gastric conditions led to the liberation of an osteoanabolic peptide. Moreover, female gut conditions were able to liberate more free amino acids from oat milk rather than from dairy milk while male conditions yielded an inverse trend.❞

Translating from sciencese:

• in the male model, cow-derived dairy milk proteins were broken down more efficiently, producing more antimicrobial peptides (that’s good, contextually)
• in the female model, oat-based plant milk proteins digested more efficiently, generating osteoanabolic peptides that are important for bone formation (that’s good in almost any context)

This becomes super-important when we note that women have, other things being equal, a much higher risk of osteoporosis than men.

You can read the paper in full here: Sex-based differences in in vitro digestibility of milk and oat drink, and powder counterparts

What about estrogen in soy milk?

That study used oat milk (which is very healthful).

However, since we’re talking plant milks and sex: many people cite the phytoestrogens in soy milk as a reason that women should drink it, and men should not. That’s half-correct:

• For women, the phytoestrogens in soy milk cannot be used as estrogen directly (not compatible with human estrogen), but it can be broken down and the parts used to make new, compatible, human estrogen (assuming you have working ovaries, to produce that estrogen).
• For men, the phytoestrogens in soy milk cannot be used as estrogen directly (not compatible with human estrogen), but it can be broken down and the parts used to make new, compatible, human testosterone (assuming you have working testes, to produce that testosterone).

This means, gentlemen-readers, that no, soy milk will not have any feminizing effect on you (unless you have ovaries instead of testes, in which case yes, it’ll boost your natural estrogen production).

See for example this research review with 439 sources of its own: Soy and Health Update: Evaluation of the Clinical and Epidemiologic Literature

You may be wondering why the “ingredients” of estrogen can be used to make testosterone. It’s because on a molecular level, they’re almost identical:

❝Both estradiol and testosterone have the “steroid nucleus” and a hydroxyl group in their structures.

Apart from estradiol, testosterone has a double bond and a ketone.❞

estradiol = the main kind of estrogen that we humans use

For the more visually-inclined, you can see the molecules diagrammed next to each other here, and play spot-the-difference!

If you’d like to explore different kinds of plant milk, we examine 6 of the best, here: Which Plant Milk?

Want to learn more?

You might want to check out this well-sourced LiveStrong article:

Bone Health: Best and Worst Foods

(Teaser: leafy greens are in 2nd place, topped by sardines at #1—where do you think dairy milk ranks?)

And if you want to dive much deeper into it than we have room to here, you’ll like this book that we reviewed a little while back; it covers today’s nutritional considerations comprehensively:

Strong Bones Forever: The Complete Drug-Free System for Preventing and Reversing Osteoporosis Using Diet, Exercise, Lifestyle, and Supplentation − by Dr. Raymond Hinish

Take care!