According to a new study by researchers at Harvard T.H. Chan School of Public Health, UC Santa Barbara, and the Global Alliance for Improved Nutrition, over half of the global population fails to meet the recommended intake levels of several essential micronutrients, including calcium, iron, and vitamins C and E. This pioneering research, slated for publication in The Lancet Global Health on August 29, offers the first global estimates of deficient consumption for 15 critical micronutrients, thereby marking a significant advancement in our understanding of nutritional deficits worldwide.
Micronutrient deficiencies are among the most prevalent forms of malnutrition worldwide, each associated with severe health repercussions. These range from negative impacts on pregnancy outcomes to increased risks of blindness and heightened vulnerability to infectious diseases. Previous studies have quantified the availability and consumption of these nutrients but have yet to evaluate whether these intakes satisfy the health requirements, especially distinguishing between the needs of males and females throughout various stages of life.
Chris Free, co-lead author and research professor at UCSB emphasizes the importance of their study, noting its novelty in estimating the inadequacy of micronutrient intakes across 34 age-sex groups in almost every country globally. Moreover, the research team has made their methodologies and findings readily accessible to both the academic community and practitioners, thereby facilitating further research and intervention planning.
The study leveraged data from the Global Dietary Database, the World Bank, and dietary recall surveys from 31 countries, assessing the nutritional needs against actual intakes among populations spanning 185 countries. The analysis covered both genders across 17 age groups, from newborns to older adults over 80, and examined 15 essential vitamins and minerals.
The results revealed widespread deficiencies, with significant gaps in the intake of iodine (68% of the global population), vitamin E (67%), calcium (66%), and iron (65%). Other nutrients like riboflavin, folate, and vitamins C and B6 also showed high levels of inadequacy, while niacin and selenium were among the less deficient nutrients. Interestingly, the study found inadequate intakes were generally higher among women than men for certain nutrients like iodine, vitamin B12, iron, and selenium, which were within the same demographic and regional brackets. Conversely, deficiencies in nutrients such as calcium, niacin, thiamin, zinc, magnesium, and several vitamins were more prevalent among men.
Patterns of deficiency varied significantly with sex. However, age also played a crucial role, especially in the 10-30-year age bracket, which showed deficient calcium intake levels, notably in South and East Asia and sub-Saharan Africa. North America, Europe, and Central Asia also recorded low levels of calcium intake.
Ty Beal, a senior technical specialist at GAIN, described the findings as alarming. They indicate that the scope of micronutrient deficiencies is even more extensive than previously recognized, affecting people across all geographic and economic categories. These deficiencies severely hinder health outcomes and limit human potential on a global scale.
Christopher Golden, senior author and associate professor of nutrition and planetary health at Harvard Chan School, underscored the enormity of the public health challenge posed by these findings. He emphasized the urgent need for health practitioners and policymakers to develop and implement targeted dietary interventions to address these deficiencies. The study also highlighted the limitations imposed by the lack of comprehensive data on individual dietary intakes globally, which could hinder the depth of future research and the effectiveness of interventions.
More information: Simone Passarelli et al, Global estimation of dietary micronutrient inadequacies: a modelling analysis, The Lancet Global Health. DOI: 10.1016/S2214-109X(24)00276-6
Journal information: The Lancet Global Health Provided by Harvard T.H. Chan School of Public Health
