Written on 25 March 2023.

The Truth About Iron Deficiency in Vegetarians and Omnivores: A Comprehensive Study

Iron is a crucial mineral that is essential for a healthy body. It is responsible for carrying oxygen to the cells and tissues in the body, and a deficiency in this mineral can lead to a wide range of health problems. While iron is found in many foods, vegetarians are often thought to be at higher risk of iron deficiency than omnivores, as animal products are a rich source of this mineral. However, a recent study has shed light on the true prevalence of iron deficiency in both vegetarian and omnivorous individuals, and the results may surprise you.

The study aimed to evaluate the serum ferritin levels and prevalence of iron deficiency in vegetarian and omnivorous individuals, considering factors that can elevate ferritin levels such as increased BMI, HOMA-IR, and hs-CRP values. A total of 1340 individuals were evaluated, including men, women who do not menstruate, and women who menstruate. The study found that the increase in BMI, HOMA-IR, and inflammation led to elevated ferritin concentrations regardless of dietary habits. Omnivores had a higher prevalence of obesity, higher ferritin levels, and a lower prevalence of iron deficiency. However, after excluding individuals with inflammation, the actual iron deficiency was not higher among vegetarians, except in women with regular menstrual cycles.

Factors That Affect Iron Levels

The data showed that nutritional status and inflammation levels affect ferritin levels and may interfere with the correct diagnosis of iron deficiency in both vegetarian and omnivorous individuals. Compared to vegetarians, women who do not menstruate and men had the same prevalence of iron deficiency when following an omnivorous diet. The study analyzes individuals based on sex and menstrual status, revealing a higher prevalence of lacto-ovo vegetarians among women who menstruate and a higher prevalence of omnivores among women who do not menstruate.

Iron Levels and Eating Habits

Serum ferritin concentrations increased with BMI and HOMA-IR values, regardless of eating habit and sex. In individuals without inflammation or insulin resistance, iron deficiency was more prevalent in vegetarian women who menstruate. The study confirmed that omnivorous individuals had higher circulating ferritin concentrations than vegetarian individuals. However, after excluding individuals with inflammation, the actual iron deficiency was not higher among vegetarians, except in women with regular menstrual cycles.

Conclusion:

After excluding the variables that interfere with the diagnosis of iron deficiency (such as obesity, inflammation, and insulin resistance), the study showed that there is no difference in the prevalence of iron deficiency between men and women who do not menstruate, whether they are omnivores or vegetarians. Only vegetarian women who menstruate had a higher prevalence of iron deficiency compared to omnivores. Studies to determine the prevalence of iron deficiency should not only consider ferritin levels but also other markers that affect this analysis. For example, when there is excess weight, inflammation, and insulin resistance (conditions more prevalent in the omnivorous population), ferritin levels increase without representing a greater amount of body iron.

The findings of this study have important implications for healthcare providers and individuals who follow a vegetarian or omnivorous.

This post is based on the original academic paper authored by Dr. Eric Slywitch, who serves as the Coordinator of the Nutrition Department at the International Vegetarian Union.

Source: Pubmed