Losing Weight Can Fix Your Knee Pain

Alex Nielen
May 5
3 min read

Knee pain is one of those annoyances that starts as a minor inconvenience and slowly becomes a daily frustration. Walking hurts. Standing up hurts. Even sitting the wrong way can make your knees sound like a bowl of Rice Krispies. If you’re carrying extra weight, here’s the hard truth: your knees aren’t just randomly giving out on you—they’re overloaded.

The good news? Losing weight can actually solve a lot of that pain. And no, this isn’t just some vague “healthy living” advice—there’s real science behind it.

Your Knees Were Not Designed to Carry Extra Weight

Think of your knees like the suspension system in a car. The more weight you pile into the vehicle, the harder the shocks have to work. Eventually, they wear out faster.

Now, apply that to your body:

Walking puts about 1.5 times your body weight on your knees.
Going downstairs or running can multiply that force to 3–4 times your weight.

So if you weigh 100 kg, a simple walk is like forcing your knees to carry 150 kg with every step. No wonder they’re protesting. Over time, this extra load leads to:

Cartilage breakdown – The smooth cushioning between bones wears away, leading to bone-on-bone grinding (aka osteoarthritis).
Chronic inflammation – Fat tissue releases chemicals that make joints swell and ache.
Muscle weakness – When your legs don’t support your weight well, your knees take the hit.

What Science Says About Weight Loss and Knee Pain

1. Losing Just 10% of Your Weight Makes a Big Difference

A study published in Arthritis Care & Research followed overweight adults with knee osteoarthritis. Those who lost at least 10% of their body weight reported significantly less pain and better mobility compared to those who lost less. Why? Less weight = less pressure on the joints. Even a modest drop (say, 20 lbs if you weigh 200) can take 30 lbs of strain off your knees with every step.

2. Weight Loss + Exercise Works Better Than Either Alone

Researchers in a 2013 Annals of Internal Medicine study split participants into three groups:

Diet-only (lost ~5% weight)
Exercise-only (no weight loss)
Diet + Exercise (lost ~5.7% weight)

The diet + exercise group had 37% less pain and moved more easily than the others. Why? Because losing fat reduces joint stress, while exercise strengthens the muscles that support your knees.

3. Preventing Knee Damage Before It Starts

The famous Framingham Study tracked adults over time and found that losing just 11 pounds cut the risk of developing knee osteoarthritis in half. That’s huge—it means you don’t have to drop massive weight to protect your joints.

How to Actually Do It

Move More, But Smarter:
Walking, swimming, and cycling are easy on the knees. Strength training (especially squats and leg presses) builds muscle to absorb shock.
Eat in a Way That Doesn’t Feel Like Punishment:
Cut back on sugar and processed foods (they increase inflammation). Eat more protein, fiber, and healthy fats to stay full and energized.
Small Changes Add Up:
You don’t need to lose 20 kg overnight. Even 5–10% of your weight (5-10 kg per a 100 kg person) reduces pain.

The Bottom Line

If your knees hurt and you’re overweight, the simplest solution is often the most effective: lose some weight. You don’t have to become a marathon runner or live on kale—just lighten the load on your joints. Your knees aren’t “just getting old.” They’re tired of carrying extra weight. Give them a break, and they might just stop complaining.