🦴 Did Our Ancestors Really Get More Calcium Than We Do?

I'm continuing the calcium series this week.

Every time I dig into one of these nutrients, the same question comes up for me. Why does it feel so hard, in modern life, to get the nutrition we actually need?

It feels like there are more and more factors working against us. We've built an environment full of stress. Our diets have narrowed, or changed so much that we are no longer intuitively getting what our bodies need. But is that really true?

It raises the question: How did people survive before us? We live longer now, and in a lot of ways, we're healthier. We grow taller than the generations before us, but we've traded their problems for a different set. Ours may be less dramatic, but they feel significant to us because they shape our daily lives.

We’re told to hit 1,000 to 1,200 mg of calcium a day, and it feels like a lot. We’re supposed to be evolved beings. Why does that seem so hard? Has this always been a problem, or are we only now running into it?

The difficulty is modern, but not because we eat less calcium than our ancestors did. It's because we lose more of it.

We load our weight on our bones far less (less natural resistance training). And if you're a woman, we now live decades past menopause, which is completely new on the anthropological timeline.

You may have heard that Stone Age diets delivered about twice the calcium we get now. But that number is based on a model, not a concrete measurement. The estimate shifts a lot depending on the assumptions you put into the model.

What we do know is what our diets looked like back then. Dietary calcium came from wild plants and game. No dairy. Almost no grain. It also came with a lot of potassium and very little salt, which keeps your blood slightly alkaline. That way your blood can neutralize the acid your food produces, instead of your bones having to give up minerals to do it.

Our food today is heavy on salt and light on potassium, and this balance works against our bone density.

Salt: Calcium and sodium travel together through your kidneys, so when your blood flushes out a big load of salt, calcium goes with it. The more salt you eat, the more calcium you lose, and we eat far more salt than our ancestors did.

Protein: Breaking down protein for fuel produces acid, and when your diet is short on plant food, your body neutralizes that acid by borrowing minerals from your bones, so the calcium that comes loose leaves in your urine. This isn't a reason to cut protein. Too little weakens bone, too. It's about balancing it with plants.

Caffeine: It sends a little extra calcium into your urine, but the amount is small, and at moderate intake, it doesn't harm bone as long as your calcium is adequate. It only becomes a concern with heavier intake, more than about two cups of coffee a day paired with a low calcium diet. The fix is getting enough calcium, not giving up coffee.

Bone is living tissue, and it responds to how much you use it.

Once people started farming and later sitting most of the day, we simply started using our bodies less.

Our bones got lighter to match that level of activity.

Our calcium system evolved to carry us through our childbearing years, not the 30 or more that many women now live after menopause. Modern life added a long stretch of low estrogen that our skeleton was never completely evolved for.

So we're not doing any of it wrong. Losing bone in these years is what happens when you live long enough to reach this stage of life. (In many ways, that is worth celebrating.)

It is common, and it is almost expected. Research is still working out how to protect bone across decades of low estrogen.

The 1,000 to 1,200 mg target is an early attempt at mitigating the problem. Studying this problem properly so that we have viable solutions is the work ahead.

🧂 Aim to keep sodium under about 2,300 mg a day, roughly one teaspoon of salt. Most of it hides in bread, deli meat, cheese, and jarred sauces; on the label, keep any single item under about 20% of the daily sodium value. Every 2,300 mg of sodium your body clears takes about 10 mg of calcium out in your urine, and most of us eat far more than a teaspoon.

🥗 Make vegetables or fruit half your plate at any meal built around meat. That's about two servings next to the protein. The alkali in plants neutralizes the acid from protein before your bones have to.

🏋️ Do resistance or impact exercise at least two days a week, and something weight-bearing every day. Lifting, carrying groceries, stairs, hopping, and brisk walking all count. Bone grows in response to the load you put on it.

🩺 If you’re concerned, ask for a bone-density (DXA) scan and a vitamin D (25-OH-D) blood test. If you're over 50, count your daily calcium against the 1,200 mg target, and pair it with the salt, produce, and movement targets above.

Here’s what caught my eye this week:

📄 Soy is the only diet change with a real signal for hot flashes, and even that is shaky: Across 15 trials in 1,952 women, soy based diets cut how often and how badly hot flashes hit, but the reviewers graded that finding very low certainty, and the broader mood and thinking benefits did not hold up. DASH, MIND and vegetarian patterns looked mildly promising for mood, though the reviewers could not pool them.

📄 A liver safety signal is building around GLP-1 drugs, mostly in women: A review gathered 31 published cases of liver injury linked to GLP-1 and GLP-1/GIP drugs plus 232 reports to the FDA's adverse event system, and most cases were in women. The symptoms looked like the nausea and belly pain the drugs cause anyway, which is how it gets missed, and liver tests usually recovered after stopping. These are case reports, so the true rate is unknown and probably still rare.

🧴 Mira opened a waitlist for an at home cortisol tracking kit: It reads cortisol in urine using the wands and app Mira already sells for hormone tracking, and builds a personal baseline over about a week of morning and evening tests. Mira states itself that cortisol is not a direct or complete measure of stress and the kit is not meant to diagnose anything.

Just sharing here what's new this week. No affiliates, no sponsorships, no freebies. A mention here isn't a recommendation.