【Brittle Bones Even When You’re Young】What Is Early-Onset Osteoporosis? How Overeating Weakens Bones and the Eating Habits That Protect Them

“Osteoporosis? Isn’t that a disease old people get?”

“I’ve never once thought about my bones while I’m still young…”

“Is there really that much of a connection between overeating and bones?”

I hear reactions like these all the time.

But in fact, bone density loss may already be quietly underway in your 30s and 40s.

And recent research has been showing that overeating and an unbalanced diet are deeply connected to bone health.

In this article, I’ll explain how overeating weakens your bones and the eating habits that protect them from a young age.

I’ll also cover the causes of early-onset osteoporosis (osteoporosis in younger people), how it’s diagnosed, and when to see a doctor.

If you’re thinking “breaking a bone is a long way off for me,” this article is especially for you.

Osteoporosis Isn’t Just an “Old Person’s Disease”: Bone Density Loss Is Rising Rapidly Among Young People

Osteoporosis has an image of being “a disease that has nothing to do with young people,” but that’s actually not the case.

Bone density peaks in your 20s and 30s and then declines with age.

In other words, building up your bone density while you’re young has a big impact on your risk of fractures in the future.

If you wait until your 40s or 50s to panic, there’s a limit to how much you can regain.

Your Bones Are Like a “Savings Account You Use for Life”

The amount of bone you have is often compared to “bone savings.”

If you build up your savings during your growth years and while you’re young, you’ll have a comfortable balance even as a little is withdrawn each year with age.

On the other hand, if your savings are small when you’re young, you’ll hit an “insufficient balance” early, even if they drop at the same pace.

That’s why the eating and lifestyle habits you have when you’re young can affect your fracture risk decades later.

The Reality of Osteoporosis: How Serious It Is, in Numbers

In Japan, it’s said that there are about 13 million people with osteoporosis.

It’s often thought of as common in women after menopause, but recently it has been increasing among young women and men too, and cases of bone density loss being found in people in their 20s are not unusual.

You could say that the complacency of “I’m still young, so I’m fine” is raising your future risk of fractures.

Why Fractures Are So Frightening

Recovering from a fracture takes a long time.

In particular, femur (hip) fractures in older adults carry a high risk of leaving people bedridden, and they’re said to even affect mortality.

But by changing your eating habits now, you can change that future.

Prevention starting from a young age leads to protecting yourself decades from now.

Bone Density Loss Causes Almost No Noticeable Symptoms

Even when your bone density drops, there are almost no signs like pain or fatigue.

That’s why many people first realize “my bones had become fragile” only after they break one.

You could say it’s like continuing to withdraw a little from your savings account every month without ever once checking the balance.

For younger generations especially, there’s great value in rethinking your eating habits while there are still no symptoms.

Men Aren’t Off the Hook Either

Osteoporosis has an image of being a women’s disease, but it also happens to men.

Because men tend to have more bone mass than women, they’re more likely to let their guard down, and when overeating, drinking too much, lack of exercise, and smoking overlap, their bone savings may shrink without them noticing.

3 Ways Overeating Weakens Your Bones

At first glance, overeating and bones don’t seem connected, do they?

But in fact, your bone health is threatened through several pathways.

Your Bones Are “Torn Down” and “Rebuilt” Every Day

Bone isn’t something that’s finished once it’s formed. Every day, it repeats a process called “bone metabolism (remodeling),” in which old bone is broken down and new bone is built.

It’s easy to understand if you compare the osteoblasts that build bone to “carpenters” and the osteoclasts that dissolve bone to a “demolition crew.”

As long as these two stay in balance, your bone mass is maintained, but when the speed of demolition outpaces rebuilding, your bones gradually become brittle and porous.

Overeating is thought to upset this balance through several routes.

① Insulin Spikes Disrupt Bone Metabolism

It’s thought that the lower your insulin sensitivity, the stronger this effect becomes.

I explain how insulin resistance builds up in detail in another article, so please give it a read.

② Too Many Acid-Forming Foods Wash Calcium Out

A diet heavy in carbohydrates, processed foods, and meat tends to tip your body toward acidity.

To neutralize that acidity, your body has a mechanism that dissolves calcium out of your bones.

In other words, your bones are also your body’s “emergency warehouse” for calcium.

As a result, calcium is excreted in your urine and your bone density gradually drops. This is one of the major reasons “overeating weakens your bones.”

You could say that balancing these with alkaline foods like vegetables and fruit is important.

③ Phosphoric Acid and Chronic Inflammation Interfere with Bone

The “phosphoric acid” found in large amounts in soft drinks (such as cola) greatly interferes with calcium absorption.

When the balance between phosphorus and calcium is disrupted, bone density loss speeds up.

Chronic inflammation from overeating may also activate osteoclasts (the cells that dissolve bone), creating a state in which bone breaks down faster than it’s built.

Imagine chronic inflammation as a small fire that keeps smoldering inside your body.

That smoldering fire keeps calling in the demolition crew, so the carpenters can’t keep up with the rebuilding.

Not Just the “Quantity” of Bone, but Its “Quality” Also Declines

Bone strength isn’t determined only by the “quantity” known as bone density.

Inside your bones, fibers called collagen run throughout like steel rebar, and the “quality” of this rebar also affects how strong your bones are.

When high blood sugar continues for a long time, “glycation,” in which sugar sticks to proteins, progresses, and this is thought to make the collagen rebar brittle.

It’s known that people with diabetes break bones more easily even when their bone density isn’t especially low, and one reason behind this is said to be a decline in bone quality.

This means that eating too many sweets and refined carbohydrates can affect both the quantity and the quality of your bones.

Modern Eating Habits That Lead to Bone Density Loss in Young People

Certain eating patterns seen especially in younger generations are raising the risk of bone density loss.

Check whether any of these points make you think, “That might be me.”

Soft Drinks and Sweets Becoming an Everyday Habit

A daily habit of drinking cola, sports drinks, or sweetened coffee does double damage to your bones.

That’s because, on top of phosphoric acid blocking calcium absorption, the sugar also causes insulin spikes.

The longer you keep “drinking them instead of water,” the more the effects on your bone density accumulate.

Too Few Vegetables and Dairy Products, and Reliance on Processed Foods

When you eat fewer calcium-rich foods (dairy products, tofu, small fish, and leafy greens), you run short of the very materials your bones are made of.

When processed and instant foods become the center of your diet, you tend to fall short across the board on the nutrients your bones need, such as calcium, magnesium, and vitamin K2.

This shows how much more important the “quality” of your meals is than their “quantity” when it comes to protecting your bones.

Combined with Lack of Exercise, the Risk Rises Even Further

Bones have the property of “becoming stronger when they’re put under moderate load (gravity and exercise)”.

You could say that the combination of overeating plus lack of exercise is the pattern that speeds up bone density loss the most.

Ideally, you should combine improving your eating habits with habits that give your bones the right stimulation, such as walking and strength training.

Extreme Dieting and Being Too Thin Also Weaken Bones

The opposite of overeating, extreme dieting where you barely eat, is also a major risk for the bones of younger generations.

That’s because when you’re too thin, less load is placed on your bones, and you’re also more likely to run short of the nutrients that are the building blocks of bone.

Women in particular are said to lose bone mass more easily when extreme food restriction disrupts their periods, because the female hormones that protect bones become less effective.

In other words, both “eating too much” and “eating too little” can drain your bone savings.

Lack of Sleep, a Night-Owl Lifestyle, and Too Little Sunlight

If you live a night-owl lifestyle and barely go outside during the day, you’re likely to run short of vitamin D, which your body makes when exposed to sunlight.

Vitamin D is the “carrier” that helps you absorb calcium, so when you’re short on it, the calcium you’ve worked to get has a harder time reaching your bones.

Late-night eating and lack of sleep also disrupt your blood sugar and hormone rhythms, so they don’t create a good environment for your bones either.

Nutrients That Support Bone Health and Ways of Eating That Block Absorption

To protect your bones, “what to cut back on and how to eat” is just as important as “what to eat.”

The 4 Key Nutrients Your Bones Need

To use a house-building analogy, calcium is the “bricks,” vitamin D is the “truck that carries the bricks,” and vitamin K2 is the “cement that holds the bricks in place.”

Increasing just one of them won’t make your bones strong if the others are lacking.

Getting a suitable amount of protein, such as meat, fish, eggs, and soy products, is also essential for making the collagen that forms the framework of your bones.

Ways of Eating That Harm Bone Health

The perspective of “reducing what gets in your bones’ way” is just as important as “doing things that are good for your bones.”

How overeating disrupts your gut environment and interferes with nutrient absorption is also relevant to bone health.

A well-balanced gut environment is a prerequisite for properly absorbing calcium and other building blocks of bone.

Bone-Friendly Eating Tips

It’s easier to keep up if you get the building blocks of bone a little at every meal rather than all at once in one meal.

For example, you could have yogurt or eggs in the morning, a side dish with small fish or tofu at lunch, and salmon, ohitashi (blanched greens in a light soy-based dressing), and natto at dinner.

Even when choosing food at a convenience store, simply pairing an onigiri (rice ball) with a boiled egg or salad and unsweetened tea, instead of a sweet pastry and a sugary drink, makes a real difference to the burden on your bones.

Rather than aiming for perfection, I recommend starting with small swaps like “one fewer sugary drink” or “one more side dish.”

Heavy Drinking and Smoking Are Also Enemies of Your Bones

Apart from food, heavy drinking and smoking are also known as lifestyle habits that weaken bones.

Drinking too much alcohol interferes with nutrient absorption, and tobacco is said to have negative effects on bone formation and female hormones.

Along with improving your diet, think about keeping alcohol to a moderate amount and moving toward quitting smoking.

Causes, Diagnosis, and When to See a Doctor for Early-Onset Osteoporosis

From here, let’s go over the basics of osteoporosis in younger people, known as early-onset osteoporosis.

It can be caused not only by eating habits but also by illnesses or medications, so it’s important to understand it correctly.

Causes Are Divided into “Primary” and “Secondary”

Osteoporosis is broadly divided into two types: “primary” and “secondary.”

Primary osteoporosis is the type mainly driven by aging, menopause, lifestyle habits, and similar factors.

Secondary osteoporosis refers to the type in which bones become weak because of other illnesses or medications.

When osteoporosis is found in premenopausal women or people under 50, it’s said that
the possibility of secondary osteoporosis caused by things like endocrine (hormone) disorders must be thoroughly investigated.

Diagnosis Is Based on “Whether There Are Fractures” and “Bone Density”

Under Japan’s diagnostic criteria, diagnosis is mainly based on two things: “whether you have a fracture caused by weak bones (a fragility fracture)” and “your bone density value.”

Bone density can be measured at medical facilities or at local government health checkups using methods such as DXA (dual-energy X-ray absorptiometry) or ultrasound.

For younger people, this can also be a chance to check whether their bone mass is low compared with others their age.

Treatment Basics: “Addressing the Cause” Plus “Diet and Exercise”

In secondary cases, treating the underlying illness that’s weakening the bones is essential.

On top of that, the basics are a diet that provides calcium, vitamin D, and vitamin K2, and exercise that stimulates the bones.

However, diet alone can’t prevent fractures, so your doctor will decide whether you need treatment with medication.

See a Doctor Early in These Cases

If you broke a bone from just a minor fall, have ongoing back or lower back pain, or feel like you’ve gotten shorter, please consult an orthopedic specialist or similar doctor early.

Women whose periods have stopped because of extreme dieting and people who have used steroid medications for a long time will also feel more at ease if they ask a doctor about their bone density once.

Rather than jumping into supplements or food restriction on your own judgment, identifying the cause together with a professional is the quickest way to protect your bones.

Frequently Asked Questions About Early-Onset Osteoporosis, Bones, and Overeating

Protect Your Health Starting with Your Bones by Changing Your Eating Habits: Approaches You Can Start Today

“Protecting your bones” may sound difficult, but in fact you can start by rethinking your eating habits.

Even if each change is small, adding them up can halt bone density loss and greatly lower your future risk of fractures.

3 Things You Can Do Starting Today to Protect Your Bones

Why Fasting Improves Bone Metabolism

Intermittent fasting (16-hour fasting) may also be beneficial for bone health.

It’s thought that setting aside time without eating lets your insulin levels settle, creating an environment in which osteoblasts (the cells that build bone) can work normally.

Also, as chronic inflammation is reduced, the overactivity of osteoclasts tends to calm down too.

However, since you eat fewer times while fasting, it’s essential to get plenty of calcium, vitamin D, and protein during your eating window.

Creating time without eating and improving the quality of what you eat during your eating window work together like the two wheels of a car when it comes to protecting your bones.

Make Today’s Meal a “Deposit” for Your Future Bones

It’s also true that bone is replaced over a long period of several months to several years, so it’s hard to feel the effects right away.

That’s exactly why you should keep going, thinking of today’s meal and today’s drink as “deposits” into the bones of your future self.

I’d also like you to read about how eating too much sugar affects aging and bone metabolism.

If you have concerns about your bones or have a chronic condition, please talk to your doctor before making major changes to how you eat.

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