Study analysis · Bone · 2019
Eating more protein could be secretly strengthening your bones — here's the shocking number.
For every extra gram of protein per kilogram of your body weight you eat daily, your bones get slightly stronger.
Overview
What the study found
The study in plain English — the bottom line, every takeaway we extracted, and what to do with them.
In simple terms
This study looked at whether people who eat more protein have stronger bones, and found a tiny link — but it didn’t make people change their diets to test it. So we can’t say eating more protein makes bones stronger, just that the two tend to go together.
What’s the bottom line?
Scientists looked at whether people who eat more protein have stronger bones, using data from over 70,000 adults.
How strong is this study?
It’s a big study with lots of people, which is good, but we don’t know how they measured food or bones exactly, and other things like exercise or age might have affected the results. That means we should be careful trusting it too much.
0 / 100
- COI disclosureconflicts of interest not disclosed
- Data availabilitydata not shared
- Code availabilitycode not shared
25 / 100
- Randomizationrandomization unclear
- Blindingblinding unclear
- Control groupno control group
- Sample size (n=70215)+20/20
- Follow-upno follow-up reported
100 / 100
77 / 100
- P-values+15/15
- Effect size+20/20
- Confidence intervals+15/15
- Pre-registrationnot pre-registered
Each component is scored out of 100 and then capped by the study design — a case series cannot reach the ceiling a randomised trial can, however well it is reported.
Where it sits
RCT reviewsReviews of RCTs (Meta-analyses)
Max 100Randomized TrialsRandomized Trials
Max 90Reviews of Cohort StudiesReviews of Cohort Studies
Max 85Cohort StudiesCohort Studies
Max 72Reviews of Case-Control StudiesReviews of Case-Control Studies
Max 63Case-Control StudiesCase-Control Studies
Max 58Cross-Sectional & Case SeriesCross-Sectional & Case Series
Max 50Expert OpinionExpert Opinion
Max 544 / 100
Probability of being correct
Snapshots of a population at a single point in time, or descriptions of small groups. Can identify correlations and prevalence, but cannot determine cause and effect.
This design cannot establish causation — the findings describe an association, not a cause. This is an observational cross-sectional study with no randomization, blinding, or control group explicitly stated. Association does not imply causation, and confounding factors cannot be fully ruled out.
No Conflicts
No conflicts of interest identified
No conflicts of interest or funding information were disclosed in the provided text.
The study uses data from the UK Biobank, a large public cohort, which typically involves independent analysis. However, without explicit disclosure of funding or COI, assumptions cannot be made beyond what is stated.
Key takeaways
- 01
For every extra gram of protein per kilogram of body weight eaten daily, bones were slightly stronger: women’s BMD went up by 0.010, men’s by 0.008.
- 02
The change is small but statistically significant, meaning it’s unlikely due to chance and may matter over time.
Practical takeaways
Aim for 1 gram of protein per kilogram of body weight daily — for a 70kg person, that’s about 70g of protein.
This study only shows correlation, not causation, and BMD was measured by ultrasound, not the gold-standard DXA scan.
low confidenceWhy this study matters
Protein = Stronger Bones, Even After Accounting for Everything Else
For every 1.0 g/kg/day increase in protein intake, women saw a 0.010 increase in bone mineral density (BMD) and men saw a 0.008 increase — and this held true even after adjusting for diet, physical activity, and demographics.
Most people think only calcium and vitamin D matter for bones — this shows protein, often ignored or feared, has a measurable, positive effect.
Want the whole report?
Detailed mode opens the full scientific breakdown — every score component, the methodology, conflicts of interest, the evidence analysis behind each claim, and the raw study data.
Overview
What the study found
The study in plain English — the bottom line, every takeaway we extracted, and what to do with them.
Not medical advice. For informational purposes only. Always consult a healthcare professional. Terms
Scientists looked at whether people who eat more protein have stronger bones, using data from over 70,000 adults.
Research results
For every extra gram of protein per kilogram of body weight eaten daily, bones were slightly stronger: women’s BMD went up by 0.010, men’s by 0.008.
What this means - more context
The change is small but statistically significant, meaning it’s unlikely due to chance and may matter over time.
The study aimed to examine the association between dietary protein intake and bone mineral density (BMD) in middle-aged adults, addressing ambiguous prior evidence.
Higher protein intake was positively and linearly associated with BMD in both men and women, independent of socio-demographic, dietary, and physical activity factors, with statistically significant effect sizes per 1.0 g/kg/day increment.
Methods Used
Baseline data from the UK Biobank (n=70,215; aged 40–69) were used; BMD was measured by ultrasound and analyzed with adjustments for confounders. Methodology details not available in abstract.
Main Finding
Per 1.0 g/kg/day increase in protein intake, BMD increased by β=0.010 (95% CI 0.005–0.015, p<0.0001) in women and β=0.008 (95% CI 0.000–0.015, p=0.044) in men.
Confidence Level
Limited - based on abstract only, full methodology not available
Study Flags
Red Flags
- •Full text not available - methodology details cannot be verified
- •BMD measured by ultrasound instead of DXA (gold standard)
- •Cross-sectional design cannot prove causation
No biological mechanisms were identified in this study. This may be an epidemiological, observational, or survey-based study that reports associations rather than proposing causal biological pathways.
Practical Takeaways
Aim for 1 gram of protein per kilogram of body weight daily — for a 70kg person, that’s about 70g of protein.
RCT reviewsReviews of RCTs (Meta-analyses)
Max 100Randomized TrialsRandomized Trials
Max 90Reviews of Cohort StudiesReviews of Cohort Studies
Max 85Cohort StudiesCohort Studies
Max 72Reviews of Case-Control StudiesReviews of Case-Control Studies
Max 63Case-Control StudiesCase-Control Studies
Max 58Cross-Sectional & Case SeriesCross-Sectional & Case Series
Max 50Expert OpinionExpert Opinion
Max 544 / 100
Probability of being correct
Snapshots of a population at a single point in time, or descriptions of small groups. Can identify correlations and prevalence, but cannot determine cause and effect.
Human Cross-Sectional
Subject
Moderate probability
on the GRADE evidence scale
This study looked at whether people who eat more protein have stronger bones, and found a tiny link — but it didn’t make people change their diets to test it. So we can’t say eating more protein makes bones stronger, just that the two tend to go together.
No conflicts of interest were detected in this study. No score impact.
Strengths
- Large sample size (n=70,215)
- Adjustment for multiple confounders (socio-demographics, lifestyle, comorbidities)
- Use of a well-established population cohort (UK Biobank)
Weaknesses
- Full methodology not available - based on abstract only
- Cross-sectional design prevents determination of temporal sequence
- No randomization or control group confirmed
Methodology
Evidence Keywords
Statistical Reporting
Not medical advice. For informational purposes only. Always consult a healthcare professional. Terms
Scientists looked at whether people who eat more protein have stronger bones, using data from over 70,000 adults.
Research results
For every extra gram of protein per kilogram of body weight eaten daily, bones were slightly stronger: women’s BMD went up by 0.010, men’s by 0.008.
What this means - more context
The change is small but statistically significant, meaning it’s unlikely due to chance and may matter over time.
The study aimed to examine the association between dietary protein intake and bone mineral density (BMD) in middle-aged adults, addressing ambiguous prior evidence.
Higher protein intake was positively and linearly associated with BMD in both men and women, independent of socio-demographic, dietary, and physical activity factors, with statistically significant effect sizes per 1.0 g/kg/day increment.
Methods Used
Baseline data from the UK Biobank (n=70,215; aged 40–69) were used; BMD was measured by ultrasound and analyzed with adjustments for confounders. Methodology details not available in abstract.
Main Finding
Per 1.0 g/kg/day increase in protein intake, BMD increased by β=0.010 (95% CI 0.005–0.015, p<0.0001) in women and β=0.008 (95% CI 0.000–0.015, p=0.044) in men.
Confidence Level
Limited - based on abstract only, full methodology not available
Study Flags
Red Flags
- •Full text not available - methodology details cannot be verified
- •BMD measured by ultrasound instead of DXA (gold standard)
- •Cross-sectional design cannot prove causation
No biological mechanisms were identified in this study. This may be an epidemiological, observational, or survey-based study that reports associations rather than proposing causal biological pathways.
Practical Takeaways
Aim for 1 gram of protein per kilogram of body weight daily — for a 70kg person, that’s about 70g of protein.
RCT reviewsReviews of RCTs (Meta-analyses)
Max 100Randomized TrialsRandomized Trials
Max 90Reviews of Cohort StudiesReviews of Cohort Studies
Max 85Cohort StudiesCohort Studies
Max 72Reviews of Case-Control StudiesReviews of Case-Control Studies
Max 63Case-Control StudiesCase-Control Studies
Max 58Cross-Sectional & Case SeriesCross-Sectional & Case Series
Max 50Expert OpinionExpert Opinion
Max 544 / 100
Probability of being correct
Snapshots of a population at a single point in time, or descriptions of small groups. Can identify correlations and prevalence, but cannot determine cause and effect.
Human Cross-Sectional
Subject
Moderate probability
on the GRADE evidence scale
This study looked at whether people who eat more protein have stronger bones, and found a tiny link — but it didn’t make people change their diets to test it. So we can’t say eating more protein makes bones stronger, just that the two tend to go together.
No conflicts of interest were detected in this study. No score impact.
Strengths
- Large sample size (n=70,215)
- Adjustment for multiple confounders (socio-demographics, lifestyle, comorbidities)
- Use of a well-established population cohort (UK Biobank)
Weaknesses
- Full methodology not available - based on abstract only
- Cross-sectional design prevents determination of temporal sequence
- No randomization or control group confirmed
Methodology
Evidence Keywords
Statistical Reporting
Scoring
How strong is this study?
It’s a big study with lots of people, which is good, but we don’t know how they measured food or bones exactly, and other things like exercise or age might have affected the results. That means we should be careful trusting it too much.
0 / 100
- COI disclosureconflicts of interest not disclosed
- Data availabilitydata not shared
- Code availabilitycode not shared
25 / 100
- Randomizationrandomization unclear
- Blindingblinding unclear
- Control groupno control group
- Sample size (n=70215)+20/20
- Follow-upno follow-up reported
100 / 100
77 / 100
- P-values+15/15
- Effect size+20/20
- Confidence intervals+15/15
- Pre-registrationnot pre-registered
Each component is scored out of 100 and then capped by the study design — a case series cannot reach the ceiling a randomised trial can, however well it is reported.
Where it sits
RCT reviewsReviews of RCTs (Meta-analyses)
Max 100Randomized TrialsRandomized Trials
Max 90Reviews of Cohort StudiesReviews of Cohort Studies
Max 85Cohort StudiesCohort Studies
Max 72Reviews of Case-Control StudiesReviews of Case-Control Studies
Max 63Case-Control StudiesCase-Control Studies
Max 58Cross-Sectional & Case SeriesCross-Sectional & Case Series
Max 50Expert OpinionExpert Opinion
Max 544 / 100
Probability of being correct
Snapshots of a population at a single point in time, or descriptions of small groups. Can identify correlations and prevalence, but cannot determine cause and effect.
This design cannot establish causation — the findings describe an association, not a cause. This is an observational cross-sectional study with no randomization, blinding, or control group explicitly stated. Association does not imply causation, and confounding factors cannot be fully ruled out.
No Conflicts
No conflicts of interest identified
No conflicts of interest or funding information were disclosed in the provided text.
The study uses data from the UK Biobank, a large public cohort, which typically involves independent analysis. However, without explicit disclosure of funding or COI, assumptions cannot be made beyond what is stated.
Standing
Who’s using this study?
The videos and claims on this site that lean on this study, and the researchers who wrote it.
1 video from Shawn Baker MD cite this study, drawing 1 claim from it.
- Very strong evidence
Randomized or controlled trials support this claim, alongside consistent supporting evidence.
Evidence
Authored by
10 researchersIf this is your work, this is how we attribute it on Fit Body Science. Lewis Steell is listed as the lead author.