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High burden of Iodine deficiency found in Israel’s first national survey


62% of school-age children and 85% of pregnant women have low iodine intakes

“High risk of impaired neurological development of the fetus in Israel”

Ministry of Health supported research effort; now, eradicating iodine deficiency will require government funding and legislation, and a government-regulated program of salt or food iodization

The first national iodine survey conducted in Israel has revealed a high burden of iodine deficiency among Israelis, posing a high risk of maternal and fetal hypothyroidism and impaired neurological development of the fetus in Israel.

The International Child Development Steering Group has identified iodine deficiency (ID) as a key global risk factor for impaired child development, and the World Health Organization’s recommends routine monitoring of population-based data on urinary iodine every five years as a means of sustainable elimination of ID. Yet Israel is among the few countries that have never performed a national iodine survey, and does not provide iodine prophylaxis, even though some of its population has suffered from ID in the past. Israel similarly lacks current data on the incidence and prevalence of thyroid disease.

Now, researchers from the Hebrew University of Jerusalem, and their colleagues at Maccabi Healthcare Services and Barzilai University Medical Center in Ashkelon in Israel, and ETH Zurich in Switzerland, with support of the Iodine Global Network, have obtained the first nationally representative data about iodine status in the Israeli population. To do this, they collected pre-discard spot-urine samples, from 1,023 school-age children and 1,074 pregnant women, representing all regions and major sectors in Israel (Arab, Jewish secular and orthodox), during 2016 at the Maccabi Healthcare Services (MHS) central laboratory.

They found a high burden of iodine deficiency in the general population: 62% of school-age children and 85% of pregnant women fall below the WHO’s adequacy range.

The median urinary iodine concentration (UIC) among Israel’s pregnant women, only 61 micrograms iodine/liter and for school-age children, the median of 83 micrograms/liter suggest that the iodine status in Israel is amongst the lowest in the world. Iodine adequacy is defined by the WHO as a population median of 150-249 micrograms/liter for pregnant women and 100-199 micrograms/liter for school-age children. Virtually no differences were seen between different ethnicities and regions of the country suggesting that low iodine status is widespread and universal throughout the country.

Adequate iodine intake is essential for thyroid function and human health throughout life. Even mild iodine deficiency might prevent children from attaining their full intellectual potential, and mild to moderate ID has been linked with decreased cognitive performance. Iodine deficiency in utero and in early childhood impairs brain development, and severe iodine deficiency causes cretinism (physical malformation, dwarfism and mental retardation) and goiter (the enlargement of the thyroid gland).

According to the researchers, the high burden of iodine insufficiency in Israel is a serious public health and clinical concern. By comparison to data from other countries with a similar extent of deficiency, these data suggest that there is a high risk of maternal and fetal hypothyroidism and impaired neurological development of the fetus in Israel. By extrapolation, given the rate of insufficiency in Israeli pregnant women, nearly all pregnant women and their children may be at risk, implying that the majority of the population could be unlikely to realize its full intellectual potential.

“The immediate implication of our findings is that we need to improve the public’s intake of iodine,” said Prof. Aron Troen, Principal Investigator at the Nutrition and Brain Health Laboratory, School of Nutrition Science, Hebrew University’s Robert H. Smith Faculty of Agriculture, Food and Environment. “It seems that as in most other countries, Israel’s food supply and our collective dietary habits do not ensure iodine sufficiency. Thus eliminating iodine deficiency and achieving optimal iodine status in Israel’s population will require a sustainable, government-regulated program of salt or food iodization. The costs are small and the benefits substantial and have been proven in over 160 countries around the world where this is done.”

Until now, isolated but persistent calls to address this issue have not translated to action, perhaps due to lack of awareness, or the unfounded but widespread belief that Israel's proximity to the sea likely prevents ID, leading to a corresponding lack of political will.

However, in the absence of a universal salt iodization program, and in light of the heavy national reliance on iodine-depleted desalinated seawater as drinking and irrigating water, the study’s results point to a major national public health problem.

The research findings were presented at The 46th Annual Meeting of the Israel Endocrine Society, which took place on March 20-21 in Ramat Gan, Israel (

According to the researchers, a universal salt iodization and monitoring program should be urgently initiated. Dr. Jonathan Arbelle, lead co-investigator from Maccabi Healthcare Services, who presented the findings at the meeting, called upon the Israel Endocrine Society to develop guidelines for clinical practitioners who care for pregnant and lactating women. “Caregivers should recommend adequate iodine intake during pregnancy and lactation, and a randomized clinical trial of risk and benefit for correction of mild-moderate iodine deficiency during pregnancy must be considered,” said Dr. Arbelle.

“A healthful diet is a foundation of a prosperous nation. The public has a right, and government has both a moral obligation and clear-cut social and economic incentive to ensure that the nation’s food supply supports the public’s health, well-being and productivity,” said Prof. Troen.

Yaniv Ovadia, the doctoral student and registered dietitian who performed the study, said, “Individuals can improve their iodine status through increased consumption of iodine-rich foods such as milk, dairy and salt water fish. They can also replace regular table salt with iodized salt." However, only a small fraction of the salt sold in Israel is iodized, and it is sold at a much higher price than regular salt, although it does not need to be. The World Health Organization and Iodine Global Network encourage mandatory, universal salt iodization, including the all discretionary household salt.  However, some countries have effectively been able to increase their iodine intakes through the use of iodized salt in processed foods, including bread and condiments, and this may be considered in Israel.  “Government action is needed to ensure that everyone has access to iodized salt, added Prof. Troen.  

These findings also highlight the critical need for routine public health surveillance, not only of iodine, but also of other nutritional and environmental exposures that determine the Israeli population’s collective health. 

“I’m pleased that the Ministry of Health has been supportive of this particular research effort, but to act on the findings and make a sustainable change will require government funding and legislation," said Prof. Troen.

The research team included doctoral student Yaniv Ovadia, Varda Nadler, Hadassa Brik, Tamar Wolf, Michael Zimmermann, Sandra Weibel, Dov Gefel, Jonathan Arbelle, and Aron Troen.

Participating institutions included the Nutrition and Brain Health Laboratory, Institute of Biochemistry, Food Sciences, and Nutrition, Robert H Smith Faculty of Agriculture, Food and Environment, Hebrew University of Jerusalem, Israel; Department of Internal Medicine "C", Barzilai Medical University Center, Israel; Central Laboratory, Maccabi Healthcare Services, Israel; and the Human Nutrition Laboratory, Department of Health Sciences and Technology, Swiss Federal Institute of Technology (ETH) Zurich, Switzerland.

The Hebrew University Nutrition and Brain Health Laboratory is a partner in EUthyroid (, an EU-funded research project to evaluate current national efforts aimed at preventing iodine deficiency disorders, which aims to provide the basis to develop appropriate measures for harmonizing and improving iodine intake in cooperation with national authorities.

FUNDING: The research was supported by grants from the Medical Research and Development Fund for Health Services – Jerusalem, and the Israel Ministry of Health Chief Scientists Office, with partial funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement No 634453, “EUthyroid”, and funding to the ETH Zurich iodine laboratory from the Iodine Global Network.

PHOTO: (Left to right) – Researchers Dov Gefel, Yaniv Ovadia, Aron Troen, and Jonathan Arbelle (Credit: Hebrew University)



High burden of Iodine deficiency found in Israel’s first national survey

Higher BMI in Adolescence May Affect Cognitive Function in Midlife


Study of Israeli adolescents also looks at impact of socioeconomic position on subsequent cognitive impairment

Overweight and obesity in adolescents have increased substantially in recent decades, and today affect a third of the adolescent population in some developed countries. While the dangers posed by high adult BMI on cognitive function in later life have been documented, the association of adolescent BMI with cognitive function in midlife has not yet been reported. (BMI, or Body Mass Index, is a calculation of a person’s weight in kilograms divided by the square of their height in meters.)

To shed light on this issue, scientists at the Hebrew University-Hadassah Braun School of Public Health and Community Medicine set out to determine the association between cumulative life course burden of high-ranked body mass index (BMI), and cognitive function in midlife. The research, which will appear in the Journal of Alzheimer’s Disease 55(3), was led by Prof. Jeremy Kark from the Braun School, in the Hebrew University of Jerusalem’s Faculty of Medicine, working with colleagues in Israel and the United States.

The researchers used weight and height data from 507 individuals tracked from over 33 years starting at age 17. The participants completed a computerized cognitive assessment at ages 48–52, and their socioeconomic position was assessed by multiple methods. Using mixed models the researchers calculated the life-course burden of BMI from age 17 to midlife, and used multiple regression to assess associations of BMI and height with global cognition and its five component domains.

In this population-based study of a Jerusalem cohort, followed longitudinally from adolescence for over 33 years, we found that higher BMI in late adolescence and the long-term cumulative burden of BMI predicted poorer cognitive function later in life. Importantly, this study shows that an impact of obesity on cognitive function in midlife may already begin in adolescence, independently of changes in BMI over the adult life course,” said the paper’s senior author, Prof.  Jeremy Kark of the Hebrew University-Hadassah Braun School of Public Health and Community Medicine.

“Our results also show that taller stature was associated with better global cognitive function, independent of childhood and adult socioeconomic position, and that height increase in late adolescence, reflecting late growth, conferred a protective effect, but among women only,” added Irit Cohen-Manheim, doctoral candidate at the Braun School and lead author.

The researchers point out that while socioeconomic position may have a particularly important role in the trajectory of a person’s lifetime cognitive function, it has rarely been adequately taken into account: “To the best of our knowledge, the association between BMI and cognition as a function of childhood and adult socioeconomic position has not been previously reported. Childhood household socioeconomic position appears to strongly modify the association between adolescent BMI and poorer cognition in midlife, the inverse association being restricted to low childhood socioeconomic position,” said Prof. Kark.

"Our results are consistent with the hypothesis that childhood living conditions, as reflected also by height, influence cognitive function later in life; however, our study is unique in showing that an adverse association of higher BMI with cognitive function appears to begin in adolescence and that it appears to be restricted to adults with lower childhood socioeconomic position,” said Prof.  Kark.

Evidence for the association between impaired cognitive function in midlife and subsequent dementia supports the clinical relevance of our results. Findings of the relation of BMI in adolescence with poorer midlife cognitive status, particularly in light of the ongoing epidemic of childhood obesity, require confirmation," said Irit Cohen-Manheim.

Scientists involved in this research are affiliated with the Hebrew University-Hadassah Braun School of Public Health and Community Medicine, Jerusalem, Israel; Department of Clinical Research, NeuroTrax Corporation, Modiin, Israel; Centre for Medical Decision Making, Ono Academic College, Kiryat Ono, Israel; Department of Neurology, Albert Einstein College of Medicine, Bronx, NY, USA; Biostatistics Unit, Gertner Institute for Epidemiology and Health Policy Research, Tel-Hashomer, Israel.

FUNDING: The research was supported by grants from the Chief Scientist of the Israel Ministry of Health, the Israel Science Foundation, and the US-Israel Binational Science Foundation to Prof. Jeremy Kark.

REFERENCE: Irit Cohen-Manheim, Glen M. Doniger, Ronit Sinnreich, Ely S. Simon, Havi Murad, Ronit Pinchas-Mizrachi and Jeremy D. Kark. Body Mass Index, Height, and Socioeconomic Position in Adolescence, Their Trajectories into Adulthood, and Cognitive Function in Midlife. The Journal of Alzheimer's Disease 55(3), article pre-published on December 6, 2016, DOI: 10.3233/JAD-160843.

The Hebrew University of Jerusalem is Israel’s leading academic and research institution, producing one-third of all civilian research in Israel. For more information, visit

Higher BMI in Adolescence May Affect Cognitive Function in Midlife

Bees Diversify Diet to Take the Sting Out of Nutritional Deficiencies

New research shows that honey bees forage for a diet that balances their colony’s specific nutritional deficits

While pesticides and pathogens pose clear threats to honey bee health, the need of bee colonies for balanced nutrition is gaining increasing appreciation. As colonies are kept in agricultural areas for crop pollination, they may encounter nutritional deficits when foraging predominantly on one pollen source. In California almond orchards for instance, 1.6 million colonies are kept every year, despite the risk of low floral diversity, which can reduce the life expectancy of bees.

In light of the challenge that agricultural intensification poses for pollinator habitats, Dr. Harmen Hendriksma and Prof. Sharoni Shafir from the Hebrew University of Jerusalem report that honey bee colonies are astoundingly resilient to nutritional stress. In new research reported in the journal Behavioral Ecology and Sociobiology, they found that bees can shift their foraging effort towards resources that complement nutritional deficits.

The research was conducted at the B. Triwaks Bee Research Center, Department of Entomology, The Robert H. Smith Faculty of Agriculture, Food and Environment, at the Hebrew University of Jerusalem.

In their experiment, eight honey bee colonies were kept in screened enclosures and fed pollen substitute diets that were deficient in particular essential amino acids. Subsequently, the bees were tested for their dietary choice, between the same diet previously fed, a different diet that was similarly deficient, or a diet that complemented the deficiency. The foragers preferred the complementary diet over the same or similar diets.

This result indicates that honey bee colonies not only attempt to diversify their diet, but that they bias their foraging effort towards a diet that specifically balances nutritional deficits of the colony. How bees perceive and evaluate nutrient composition needs further elucidation. This new-found ability of honey bees to counter deficient nutrition contributes to mechanisms that social insects use to sustain homeostasis at the colony level.

“This research indicates that honey bee colonies strive to balance their nutrition if appropriate floral resources are available. Bee colonies can benefit by this type of resilience when food options are sparse, for instance at certain sites or in seasons of dearth. Since alternative floral resources can help bees to balance their nutritional needs, this should serve as an incentive for everyone to plant flowers, wherever and whenever they can,” said Dr. Harmen Hendriksma.

“Our research with bees continues to reveal their remarkable abilities. Honey bee colonies must maintain a balanced diet for optimal health, and bee foragers seem to have evolved the sophisticated ability to bias their efforts towards finding food that balances the colony’s nutritional deficiencies. In so doing they remind us that in nutrition, as in many other things, maintaining the proper balance is key,” said Prof. Sharoni Shafir.

The Hebrew University of Jerusalem is Israel’s leading academic and research institution, producing one-third of all civilian research in Israel. For more information, visit

VIDEO 1: - Honey bee workers in this video hover over feeding dishes with different diets. While flying, bees may distinguish differences by sight and by scent. Here, bees were given a choice between 34 different diets. Notably, protein content was found least explanatory for their choice behavior, while their preference was best explained by the foods color intensity and caloric contents (please see the supplements to the paper).  (Video credit: Harmen P Hendriksma)

VIDEO 2: - Honey bee workers in this video are collecting diet from feeding dishes. Bees touch the diet with their antennas, their feet, and mouth parts. Bees have receptors on these body parts, and it is likely that bees are probing the diet for taste, smell and texture. (Video credit: Harmen P Hendriksma)

FUNDING: The research was funded jointly by a grant from the BBSRC, NERC, the Wellcome Trust, Defra, and the Scottish Government under the Insect Pollinators Initiative (grant no: BB/I000968/1), and with partial support from the Orion Foundation.

REFERENCE: Harmen P. Hendriksma , Sharoni Shafir. Honey bee foragers balance colony nutritional deficiencies. Behavioral Ecology and Sociobiology. April 2016, Volume 70, Issue 4, pp 509-517.  doi:10.1007/s00265-016-2067-5 (link:

Bees Diversify Diet to Take the Sting Out of Nutritional Deficiencies
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