Is there a relationship between how much creatine women get from food and measures of reproductive health?

A 2024 study using data from the National Health and Nutrition Examination Survey (NHANES) set out to explore that question across a large U.S. population. Rather than focusing on supplementation or controlled interventions, the researchers examined everyday dietary intake and how it relates to reported reproductive health outcomes. 

What This Study Looked At

The analysis included 4,522 women in the United States aged 12 and older who provided both dietary and reproductive health data. 

Researchers excluded supplements to focus solely on dietary creatine from meat and dairy, expressing all intake data relative to the participants' body weight. 

Participants were grouped into two categories: 

• Suboptimal intake: Those who had less than 13 mg of creatine per kilogram of body weight per day. This group made up 71% of the study population. 

• Recommended intake: Those who had at least 13 mg of creatine per kilogram of body weight per day. This group made up 29% of the study population. 

Researchers then compared these groups across several reported outcomes, including: 

• Menstrual regularity

• Pregnancy-related concerns

• Pelvic health 

• Surgical history (such as hysterectomy or oopherectomy) 

• Hormone therapy use 

What Stood Out in the Data 

Menstrual Patterns

Women in the higher intake group were less likely to report irregular menstrual cycles. 

Compared to those with lower intake, they showed about a 25% lower likelihood of reporting irregular periods (OR: 0.75). 

On average, women who reported regular cycles also consumed slightly more creatine per day—about 1.3 mg per kilogram of body weight per day than women reporting irregular cycles. 

Pregnancy-Related Outcomes 

Some differences appeared in pregnancy-related measures, while others did not. 

Women in the lower intake group were more likely to report fetal macrosomia (higher birth weight). 

This group showed about a 26% higher likelihood of this outcome compared to the women in the higher intake group. (OR: 1.26) 

At the same time, no meaningful differences were found between the groups in gestational diabetes or failed pregnancy. 

Pelvic Health and Surgical History 

The study found that lower creatine intake was associated with higher reported rates of several conditions and procedures.

• Pelvic infection: about a 68% higher likelihood (OR: 1.68) 

• Hysterectomy: about a 42% higher likelihood (OR: 1.42)

• Oophorectomy: about a 54% higher likelihood (OR: 1.54) 

These differences were observed when comparing women from the suboptimal intake group to the women in the recommended intake group. 

Hormone Therapy 

Women in the suboptimal intake group were more likely to report hormone replacement therapy use. This group showed about a 26% higher likelihood compared to the recommended intake group. 

How Researchers Interpreted the Findings 

The study describes these relationships as associations, not cause-and-effect. The observed differences remained statistically significant even after adjusting for other factors such as: 

• Dietary factors like vitamin and mineral intake 

• Demographic factors like age, income, and body mass index

This suggests the patterns were not fully explained by those factors alone. 

Important Limitations

There are several crucial constraints to keep in mind: 

• The study is cross-sectional, meaning it’s only capturing a single point in time and cannot establish causation. 

• Data on diet and reproductive health were self-reported, which may introduce inaccuracies. 

• Creatine intake estimates were based on food data only and did not include supplements. 

• The recommended intake of 13mg per kilogram per day is based on limited prior research

To Sum Up 

This study examined how dietary creatine intake relates to reported health outcomes in a large sample of U.S. women. 

Most participants consumed less than the study’s defined intake threshold of creatine. Differences were observed between intake groups across several measures, including menstrual patterns and certain reproductive health indicators, while other outcomes showed no significant variation. 

The findings add up to a limited body of population-level data and point to the need for further research to better understand these relationships.