Occurrence and Risk of Metal(loid)s in Thelesperma megapotamicum Tea Plant

This study reports on the harvesting, ingestion, and contamination of American Indian tea Thelesperma megapotamicum grown on the Navajo Reservation in New Mexico. Uranium (U) and co-metal(loid)s (As, Cd, Cs, Mo, Pb, Se, Th, and V) have contaminated local soil and plants. Tea plants were gathered for analysis near U mining impacted areas. The study collected samples of wild tea plants (n = 14), roots (n = 14), and soil (n = 12) that were analyzed with inductively coupled plasma mass spectrometry. Tea harvesting activities, behavior, and ingestion information were collected via questionnaires. Harvesting took place in community fields and near roadways. Results indicate edible foliage concentration levels for Cd exceeded the World Health Organization (WHO) raw medicinal plant permissible level guidelines. Tea samples collected near high traffic areas had significantly greater Cd and Mo concentrations than those collected near low traffic areas (p < 0.001). Tea sample metal(loid) concentration levels ranged from 0.019–7.916 mg/kg. When compared to established food guidelines including the WHO provisional tolerable weekly intake (PTWI), reference dietary intake, recommended dietary allowance, and the tolerable upper limit (UL), Cd exceeded the WHO guidelines but none exceeded the PTWI nor the UL. These findings warrant improved standardization and establishment of universal guidelines for metal(loid) intake in food.

Dietary Iron Intake and Anemia Are Weakly Associated, Limiting Effective Iron Fortification Strategies in India

BACKGROUND

Anemia prevalence in India remains high despite preventive iron supplementation programs. Consequently, concurrent national policies of iron fortification of staple foods have been initiated.

OBJECTIVES

This study evaluated the relation between dietary iron intake and anemia (hemoglobin <12 g/dL) in women of reproductive age (WRA; 15-49 y) with respect to iron fortification in India.

METHODS

Data from 2 national surveys were used. Data on hemoglobin in WRA were sourced from the National Family Health Survey-4, whereas dietary intakes were sourced from the National Sample Survey. Adjusted odds for anemia with increasing iron intake were estimated, along with the effect of modulating nutrients such as vitamins B-12 and C, from statistically matched household data from the 2 surveys. The risks of inadequate (less than the Estimated Average Requirement for WRA) and excess (more than the tolerable upper limit for WRA) intakes of iron were estimated by the probability approach.

RESULTS

The relation between iron intake and the odds of anemia was weak (OR: 0.992; 95% CI: 0.991, 0.994); increasing iron intake by 10 mg/d reduced the odds of anemia by 8%. Phytate and vitamin B-12 and C intakes modified this relation by reducing the odds by 1.5% when vitamin B-12 and C intakes were set at 2 μg/d and 40 mg/d, respectively. The additional intake of 10 mg/d of fortified iron reduced the risk of dietary iron inadequacy from 24-94% to 9-39% across states, with no risk of excess iron intake. Approximately doubling this additional iron intake reduced the risk of inadequacy to 2-12%, but the risk of excess intake reached 22%.

CONCLUSIONS

Providing fortified iron alone may not result in substantial anemia reduction among WRA in India and could have variable benefits and risks across states. Geographically nuanced dietary strategies that include limited fortification and the intake of other beneficial nutrients should be carefully considered.

Estimation of the Prevalence of Inadequate and Excessive Iodine Intakes in School-Age Children from the Adjusted Distribution of Urinary Iodine Concentrations from Population Surveys

BACKGROUND

The urinary iodine concentration (UIC), a biomarker of iodine intake, is used to assess population iodine status by deriving the median UIC, but this does not quantify the percentage of individuals with habitually deficient or excess iodine intakes. Individuals with a UIC <100 μg/L or ≥300 μg/L are often incorrectly classified as having deficient or excess intakes, but this likely overestimates the true prevalence.

OBJECTIVE

Our aim was to estimate the prevalence of inadequate and excess iodine intake in children (aged 4-14 y) with the distribution of spot UIC from iodine surveys.

METHODS

With the use of data from national iodine studies (Kuwait, Oman, Thailand, and Qatar) and a regional study (China) in children (n = 6117) in which a repeat UIC was obtained in a subsample (n = 1060), we calculated daily iodine intake from spot UICs from the relation between body weight and 24-h urine volume and within-person variation by using the repeat UIC. We also estimated pooled external within-person proportion of total variances by region. We used within-person variance proportions to obtain the prevalence of inadequate or excess usual iodine intake by using the Estimated Average Requirement (EAR)/Tolerable Upper Intake Level (UL) cutoff method.

RESULTS

Median UICs in Kuwait, Oman, China, Thailand, and Qatar were 132, 192, 199, 262, and 333 μg/L, respectively. Internal within-person variance proportions ranged from 25.0% to 80.0%, and pooled regional external estimates ranged from 40.4% to 77.5%. The prevalence of inadequate and excess intakes as defined by the adjusted EAR/UL cutoff method was ∼45-99% lower than those defined by a spot UIC <100 μg/L or ≥300 μg/L (P < 0.01).

CONCLUSIONS

Applying the EAR/UL cutoff method to iodine intakes from adjusted UIC distributions is a promising approach to estimate the number of individuals with deficient or excess iodine intakes.

Older adults need guidance to meet nutritional recommendations

OBJECTIVE

The purpose of this study was to compare the diet of healthy, free-living senior volunteers to the dietary reference intakes (DRIs) and Food Guide Pyramid recommendations.

METHODS

This study was a cross-sectional assessment of dietary habits, as measured using a standardized food frequency questionnaire, among 1,740 healthy Southwestern U.S. adults, aged 51 to 85 years. Assessment of independently-living volunteers to chemoprevention trials provides an efficient mechanism to profile typical dietary habits among the older adult population.

RESULTS

Daily estimated macronutrient intakes exceeded recommended proportions of protein and fat. In contrast, more than 60% of this senior population reported dietary vitamin D, vitamin E, folate and calcium intakes below estimated average requirements (EAR). Based on the Food Guide Pyramid recommendations, fewer than 10% of the older adults consumed the recommended daily dairy and grain servings. More females than males consumed recommended vegetable (49% versus 40%) and fruit (53% versus 48%) servings (p < 0.05). More males consumed recommended grain (11% versus 7%) and protein (78% versus 73%) servings (p < 0.05) than females.

CONCLUSIONS

Mean micronutrient intakes compared well with DRIs, although fewer than one-half of these older adults consumed recommended levels for vitamin D, vitamin E, folate, and calcium or daily food servings of dairy, grains, vegetables or fruits. Since the beneficial aspects of foods are not limited to essential nutrients, nutrition recommendations to older adults may be improved by emphasizing daily servings of nutrient-dense choices within the Food Pyramid.