Who Is At Risk for Plantar Fasciitis
Individuals at highest risk for plantar fasciitis include those with elevated body mass index (BMI ≥25 kg/m²), middle-aged adults (40-65 years), runners exceeding 40 km per week, those with occupations requiring prolonged standing/walking, and people with increased ankle plantarflexion range of motion or gastrocnemius muscle tightness.
Primary Risk Factors
Body Mass and Obesity
Obesity represents one of the strongest modifiable risk factors. Each 5-unit increase in BMI substantially elevates risk—individuals with BMI 25-30 kg/m² have 1.5-fold increased odds, BMI 30-35 kg/m² carries 2.1-fold risk, and BMI ≥35 kg/m² confers 2.7-fold higher odds of developing plantar fasciitis 1. Meta-analysis confirms increased body mass (weighted mean difference = 4.52 kg) and BMI (weighted mean difference = 2.13 kg/m²) as independent risk factors 2.
Age and Sex
- Peak prevalence occurs between ages 40-65 years 1, 3
- Those aged 40-55 years have 2.15-fold increased odds 3
- Those aged 56-65 years have 3.58-fold increased odds 3
- Females demonstrate higher prevalence overall (odds ratio = 1.35), with women ≥65 years showing the highest prevalence at 19.8% 1
- Paradoxically, being male predicted lower rates in one cohort (odds ratio = 0.52) 3
Running and Physical Activity
Runners who exceed 40 km per week have six times higher odds of plantar fasciitis compared to those running 6-20 km weekly 4. The overall incidence in runners is 2.5% versus 2.0% in non-runners, though this difference is not statistically significant 4. Moderate weekly running volumes appear protective compared to high-volume training.
Occupational Factors
Jobs requiring prolonged standing or walking dramatically increase risk:
- Great amounts of standing/walking: 3.17-fold increased odds 3
- Moderate amounts of standing/walking: 1.83-fold increased odds 3
- Healthcare workers, teachers, and military personnel represent high-risk occupational groups 3
Biomechanical Risk Factors
Ankle and Foot Mechanics
Increased plantarflexion range of motion is a significant risk factor (weighted mean difference = 7.04°) 2. Greater maximal ankle eversion during stance phase increases plantar fasciitis risk in runners 4. Conversely, more toeing out of the foot relative to the shank may be protective 4.
Muscle Weakness and Tightness
Weakness of the gastrocnemius, soleus, and intrinsic foot muscles confers 7.39-fold increased odds 3. This represents one of the strongest biomechanical predictors identified.
Foot Structure
- Pes planus (low arches/flat feet) increases susceptibility 3
- Foot deformities that significantly increase plantar pressure 5
Medical Comorbidities
Diabetes Mellitus
Diabetic patients face particular risk due to common comorbidities including obesity, sedentary lifestyle, and loss of protective sensation 6. The IWGDF guidelines extensively address plantar complications in diabetic populations, though these focus primarily on ulceration risk [5-5].
Other Systemic Conditions
- Hypertension: 1.54-fold increased odds 1
- Osteoporosis: 1.75-fold increased odds overall; 2.00-fold in women specifically 1
- History of kidney stones: 1.52-fold increased odds 1
Clinical Implications
The evidence clearly identifies modifiable versus non-modifiable risk factors. Weight reduction, appropriate footwear, activity modification (avoiding excessive running volumes >40 km/week), and addressing muscle weakness/tightness represent the most actionable preventive strategies. For high-risk occupations, implementing regular breaks from prolonged standing and using supportive footwear becomes critical.
Common pitfall: Assuming all physically active individuals have equal risk—the dose-response relationship with running volume is clear, with moderate activity potentially protective but high volumes (>40 km/week) substantially increasing risk 4.
The 11.1% prevalence in the general U.S. adult population 1 and 37% prevalence in the Jazan region study 3 underscore the substantial public health burden, particularly in middle-aged, overweight individuals with occupational exposure to prolonged weight-bearing.