Iodine, Over a third of the global population is exposed to iodine deficiency, especially in the mountains.
Most common global preventable cause of mental impairment
Iodine deficiency
https://www.who.int/data/nutrition/nlis/info/iodine-deficiency
Serious iodine deficiency during pregnancy can result in stillbirth, spontaneous abortion and congenital abnormalities such as cretinism
Role of Iodine in Metabolism
https://pubmed.ncbi.nlm.nih.gov/28103777/
Urinary Iodine Concentration
https://www.kcl.ac.uk/open-global/biomarkers/mineral/iodine/urinary-iodine-concentration
In healthy, iodine-replete adults more than 90% of dietary iodine is absorbed from the small intestine and more than 90% is excreted within 24-48 hours
Functions
Control of metabolic rate, energy levels, weight management, brain function, cardiovascular health, foetal and child development, reduced still births, infection protection in children, breast, ovary, uterus protection, prostate.
Many organs can also actively accumulate iodine: salivary glands, stomach, lactating mammary gland, ovary, prostate, pancreas.
Recommended dietary intake,150 μg/day
The correlation between iodine and metabolism: a review
https://pmc.ncbi.nlm.nih.gov/articles/PMC10985161/
Changes in Dietary Iodine Explains Increasing Incidence of Breast Cancer with Distant Involvement in Young Women
https://pmc.ncbi.nlm.nih.gov/articles/PMC5327366/
Fibrocystic breast disease
Iodine deficiency is associated with fibrocystic breast disease
Fibrocystic breast disease can be effectively treated with iodine
Fibrocystic breast disease affects at least 50% of women of child-bearing age,
and is associated with an increased risk of developing breast cancer.
Breast cancer
Increasing breast cancer in younger women since mid-1970s
Often presenting late
Iodine deficiency has been proposed to play a causative role in the development of breast cancer
Dietary iodine has also been previously proposed to play a protective role in breast cancer
Japanese women, have exceptionally low incidence of breast cancer
Emigration of Japanese women, adopting a western diet, associated with higher breast cancer rates.
Iodine is taken up by the sodium/iodide symporter in the breast
This is important in promoting the development of normal versus neoplastic breast tissue development
Reduce breast cancer
Vit D and K2, phytonutrients, cruciferous veg, cauliflower, cabbage, kale, garden cress, bok choy, broccoli, Brussels sprouts, omega 3
Mechanism of action of iodine’s anticancer effect
Antioxidant, iodide has been found to be highly efficient in scavenging reactive oxygen species
Iodine also has well-known anti-inflammatory and immunomodulatory effects
Iodine promotes differential apoptosis
Iodine promotes of P53 tumour suppressor gene activity
Iodine plays a role in the development and maintenance of healthy breast tissue
Women with goitre have three times more breast cancer
Iodine deficiency results in “hyperresponsiveness” to oestrogen, resulting in increased cell proliferation, abnormal changes within nuclei,
Iodine is necessary for breast remodelling during lactation, and pregnancy
Young women and pregnant women, have lower urinary iodine levels than men of similar age.
Women of childbearing age exhibited the lowest urinary iodine levels of any age group.
Atypia is seen more in iodine deficiency in human and animal models
Temporal Changes in Body Iodine
There has been a drop in urinary iodine in young women as well as in the general population, since the 1970s
Nutrition Examination Surveys,
A significant decrease in urinary iodine levels in the overall population during the period 1988-1994 as compared to the period 1971-1974 (P less than 0.0001).
Percentage of people with iodine deficiency, (below 50 μg/L)
(WHO recommend 100- 199 – 249 μg/liter urinary iodine, less than 100 μg/L indicates that the population’s iodine intake is insufficient.)
1971-1974
2.6% during the period
1988-1994
14.5% of the population iodine deficient by WHO criteria,
representing a 5.6-fold increase since early 1970s
Females showed a higher frequency of iodine deficiency than males (15.1% versus 8.1%).
Lower Urinary iodine levels in black relative to white women may also explain the greater increase in frequency of distant breast cancer in black women
2005-2008
Pregnant women had median urinary iodine levels of 125 μg/liter,
and 56.9% had levels less than the WHO recommended 150-249 μg/liter
Lancet, 2013
https://pubmed.ncbi.nlm.nih.gov/23706508/
I
Source