Strip away the skin, fascia, muscles, organs, blood vessels of a human and you’re left with the bones: the foundation providing passive structural support. Many people accept that we can affect and even control the health of the rest of our tissues. Muscles? Just lift. Cardiovascular system? Do some cardio and lose weight. Teeth? Stop sugar. But bones just wear down the older you get. Everyone knows it. And sometimes bones just break. There’s nothing you can to prevent it and nothing you can do to improve your healing  except wait and hope. If you want stronger bones, you’ll need some pharmacological assistance provided by a white coat-clad adult wielding a prescription pad.
But bones aren’t inert. They are living metabolic tissue. And though we can’t tell them what to do directly, they grow—or diminish—in response to the signals we send. What kind of signals should we be sending?
1. Lift hard and move quickly
Bones respond to intensity. Forceful impacts, heavy weights, high mechanical loading—these are a few of your osteoblasts’ favorite things. They are unmistakable signals that trigger your bones to begin fortifying themselves.
In one study , researchers attached activity monitors to the hips of adolescent boys and girls. As they went about their week, the monitors tracked their exposure to forceful impacts. People whose hips experienced impacts of 4.2 Gs (activities like 10 minute mile runs or 15 inch box jumps qualify) or greater had the sturdiest hips. Next, they attached monitors to a group of women over 60 and ran them through an aerobics class consisting of brisk walking and box stepping. None of the older women experienced an impact over 2.1 Gs, yet they still saw bone density benefits.
Old bones respond to the same training signals. For instance, older endurance runners have lower bone density  than age-matched sprinters, and senior athletes who engage in high-impact activity have higher bone density .
But older adults don’t have to join CrossFit to start seeing benefits to their bone density. Another study  found that premenopausal women aged 35-50 who hopped in place 20 to 40 times a day (broken up into two sets of 10 or 20 with 30 seconds of rest in between hops) for 16 weeks experienced improvements to their hip bone density; those hopping 40 times a day saw bigger improvements. That’s very doable. And if you’re a postmenopausal woman (at greater risk for osteoporosis than premenopausal), you can throw on a weight vest when you do your hops .
The very best type of training for all ages  is a combination of “impact training” and resistance exercise.
With regards to changes in bone density, exercise is site specific . Only the bones you subject to stress will respond.
2. Animal protein is safe and good to eat, so chow down
Go to any online vegan community and you’ll hear that animal protein leaches calcium from our bones. To support this assertion, they’ll cite studies showing that increased meat intakes lead to increased urinary output of calcium. So, is that steak you ate yesterday making you piss out desiccated femur?
No. Increased protein intake actually increases calcium absorption, and researchers who’ve looked into the situation closely conclude  that, as bone health is linked to lean muscle mass, activity levels, and physical strength, the average protein intake is inadequate for optimal bone health especially among the elderly. If anything, “more concern should be focused on increasing fruit and vegetable intake rather than reducing protein sources.” Meanwhile, older men with the lowest protein intakes tend to have the greatest bone loss .
The reverse is true. Animal protein  protects and strengthens bones and you should make sure to eat enough of it if you’re interested in preserving and/or building bone health.
3. Dairy helps, so give it a chance if you can
Dairy gets a bad rap. It’s “acidic.” It “leaches calcium” from your bones. You “can’t absorb” the calcium it does contain.
Dairy actually isn’t acidic , nor does it leach calcium from the bones. And dairy-bound calcium is perfectly absorbable  by humans. Most serious researchers recommend that older people at risk for osteoporosis consume more dairy , not less. In fact, people who can’t consume dairy because of an allergy have lower bone mineral density . Upon desensitization therapy and resumption of dairy consumption, bone mineral density recovers.
For optimal results, eat dairy that contains additional bone-friendly nutrients, like gouda cheese (with vitamin K2) or yogurt/kefir (which seem to induce more favorable changes  to bone metabolism than unfermented dairy).
4. Maintain good sleep hygiene
Yeah, yeah. Sleep’s important, Sisson. We get it. But allow me to display just how high quality sleep—or the lack thereof, rather—affects bone health.
- In older folks , self-reported sleep duration is inversely associated with osteoporosis. Less sleep leads to greater bone loss. More sleep protects against it.
- Melatonin, the hormone that induces sleepiness at night, plays a huge role in bone metabolism. For instance, removing a rat’s pineal gland (which produces melatonin) significantly lowers their bone mineral density .
- Obstructive sleep apnea, a disorder characterized by frequent cessations of breathing during sleep and an overall lower quality of sleep, is independently associated with low bone mineral density .
- Too much or too little sleep are both linked to osteoporosis , with daily sleep durations of 7-8 hours, 9-10 hours, and 10 hours all showing a relationship to low bone mineral density.
We can’t know if this is a causal association, of course. Osteoporosis and one’s sleep needs may have a common determinant. But given the role melatonin plays in bone metabolism, optimizing sleep and circadian rhythm is a good idea. Either way, lack or excess of sleep is probably an indication that bone health may be compromised.
5. Drink mineral water
Historically, all water was mineral water. Whether it came from mountain springs or local wells, water came imbued with magnesium, calcium, and other trace minerals. But water loaded with minerals like calcium and magnesium is hard water; it’s bad for lathering soap, it leaves mineral films on dishes and pans, it can gunk up plumbing, and it has a distinct taste (which means “tastes bad” to many people). Thus, most tap water is softened and most bottled water is glorified tap water, filtered to remove “impurities” (which include minerals). And some people, fearing fluoride and other nebulous elements, drink distilled or reverse-osmosis filtered waters containing essentially no minerals at all. This leads to lower bone-friendly mineral intakes and a host of health issues (PDF ).
Meanwhile, areas with high mineral content tap water tend to have lower rates of many degenerative diseases, including osteoporosis (PDF ). Calcium in mineral water is highly bioavailable, equivalent to the calcium in milk . Magnesium, too. Both minerals are extremely important for bone health and mineral water is an effective, delicious way to obtain more of them. You don’t even have to change your behavior much. You’re already drinking water; it’s a fundamental requirement for biological organisms. Just drink a different kind of water. I suggest Gerolsteiner, a German brand loaded with calcium and magnesium that comes in glass bottles.
A mineral water habit can get expensive, though. Consider making your own .
6. Get enough of these specific nutrients and foods
Melatonin: Getting plenty of full natural light when you wake and throughout the day, avoiding blue light in the evening , and getting to sleep at a normal, consistent time promote healthy melatonin production, but supplemental melatonin has also been shown to improve bone metabolism and health  and even counteract osteopenia . Are the people who benefit most from supplementation doing everything they can to optimize circadian health? Probably not. Does melatonin work? Yes. Just make sure to take it when you’d normally make it—an hour before bedtime.
Cod liver oil: If you want to supplement vitamin A, stick to cod liver oil, which has the correct pre-formed retinol form and enough vitamin D to balance your intake. Isolated vitamin A supplementation without concomitant vitamin D tends to perform poorly , while high retinol levels achieved via cod liver oil do not contribute to poor bone health .
Blackstrap molasses: For a triple whammy of bone supporting nutrients, have a tablespoon of blackstrap molasses . Just one will give you 180 mg of calcium, at least 48 mg of magnesium (and I’ve seen brands  that give almost 100 mg per tablespoon), and about 20% of your daily copper needs.
Gelatin or collagen: People don’t often realize that collagen makes up a significant portion of the bone matrix. Without collagen present, bone would be overly hard and likely brittle (PDF ). Collagen provides elasticity, not enough that you could make the Fantastic Four but enough that your tibia doesn’t shatter at the slightest provocation. I prefer gelatin over collagen hydrolysate because you can use the former to make fantastic sauces, curries, and gravies, but either one provides the basic collagenous building blocks that we use to make bone. Eating enough gelatin can also offset the inflammatory load caused by excessive amounts of methionine, the amino acid found abundantly in muscle meat.
Vitamin D, vitamin A, and vitamin K2: The Third Triumvirate, these three synergistically promote healthy bone metabolism. Both vitamin D and vitamin K2 have been shown to improve osteoporosis, and people often say that vitamin A is bad for bone health, but they actually promote better bones when obtained together . For vitamin D, get sun exposure or supplement to reach a blood level between 30-50 ng/dL. For vitamin A, eat liver once a week or take the aforementioned cod liver oil (which is also a source of vitamin D). For vitamin K2, eat natto, gouda, and goose liver.
Leafy greens: Greens like kale and spinach contains important minerals (calcium and magnesium) and polyphenols for bone health and inflammation.
Small bony fish: Bone-in fish like sardines provide the important pro-bone trio of animal protein, anti-inflammatory omega-3s, and bioavailable calcium.
Also, check the list of pro-bone nutrients, vitamins, and supplements listed in the recent Dear Mark post . Those that increase the healing of broken bones will also fortify otherwise healthy ones.
7. Avoid chronic inflammation
There’s strong evidence (both mechanistic and observational) that inflammation and bone health are linked.
- Eating too many omega-6 PUFAs and too few omega-3s  can increase inflammation and inhibit the creation of new bone cells .
- Being obese imparts a low-grade inflammatory state  that impairs bone growth in teen girls and associates with osteoporosis in older adults .
- Elevated circulating CRP is consistently associated  with osteoporosis.
8. Eat lots of produce
Amid all the hullabaloo regarding the relationships of animal protein, dairy, and other “controversial” foods with osteoporosis, everyone can agree that fruit and vegetable consumption has a positive connection to bone health. Study  after study  shows that greater intakes of fruit and vegetable (and potassium and magnesium which are markers for produce intake) predict better bone health .
There was even a controlled trial from earlier this year that found a diet consisting of vegetation known to have specific bone-friendly micronutrients and compounds—bok choy, red lettuce, Chinese cabbage, citrus fruits, parsley, sage, rosemary, and thyme—improved bone metabolism biomarkers compared to a control diet and an intervention diet full of regular old vegetation (PDF ).
It’s a good idea to focus on phytonutrient-rich produce. Think colorful fruits and vegetables , like purple potatoes, cabbage, and carrots and berries of all kinds. even extra virgin olive oil contains a polyphenol with bone-promoting effects .
Sound like a lot to take in? For the big takeaways, the interventions that provide the most benefit, the things you can tell your mom (or yourself) to start doing and expect actual results without getting bogged down in the details, try the following:
- Lift heavy things twice a week. “Heavy” is relative (it just has to be heavy for you, not for Internet lifting board denizens). Even “things” is relative (it could be your own bodyweight, which isn’t an external thing in the normal sense of the word). But “lift” is unequivocal.
- Expose your body to strong but manageable impacts. Sprinting will do it. Olympic lifting, box jumps, jump squats, playing sports will do it. But so will simply hopping in place, if that’s what you can manage.
- Perform but don’t rely on low-impact exercise. Biking, swimming, and brisk walking are great ways to stay active and get in shape, but they don’t exert enough impact to stimulate bone strengthening.
- Obtain enough calcium (600-1000 mg), magnesium (400 mg), and trace minerals. A liter of Gerolsteiner would get you on your way. High quality full-fat dairy and leafy greens round out the rest.
- Obtain enough vitamin D, vitamin A, and vitamin K2. Get regular sun exposure or take a vitamin D3 supplement (vitamin D). Eat liver once a week or supplement with cod liver oil (vitamin A). Eat natto and gouda regularly (vitamin K2). To be sure, take a vitamin K2 supplement, since not everyone can stomach natto and I wouldn’t trust my K2 intake entirely to gouda.
- Eat a variety of colorful fruits, vegetables, spices, and herbs. These provide important minerals, vitamins, phytonutrients, and antioxidant compounds that can reduce inflammation and improve bone health.
- Avoid chronic inflammation.
- If poor bone health is present, look into some of the supplements listed.
The longer you wait to enact these changes, the more interventions you’ll have to introduce. It’s easier to keep what you have than get back what you’ve lost.
What about you, folks? How do you address bone health? Since going Primal, has your bone density improved (if you’ve checked)?
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