HIGH HOMOCYSTEINE, CARDIOVASCULAR RISK AND DIET

Hyperhomocysteinemia (high blood levels of homocysteine) is an emerging cardiovascular risk factor, which may depend on nutrient deficiencies in the diet.

Some nutrients (choline, betaine and some B-group vitamins) are essential to keep homocysteine blood levels under control and for this reason they can boast the Health Claim "contributes to normal homocysteine metabolism " , authorized by the European Food Safety Authority (EFSA) on the basis of substantial scientific evidence.

Homocysteine is a non-protein amino acid biosynthesized during metabolism of methionine, an essential sulfur amino acid that is taken with diet.

The blood level of homocysteine is the result of a close relationship between dietary habits and genetic predisposing factors and an high level of homocysteine in the blood may depend on the lack of folate and other B-group vitamins in the diet.

Hyperhomocysteinemia (high blood levels of homocysteine) is now considered an emerging, strong and independent cardiovascular risk factor , associated with the onset of cardiovascular disease (coronary atherosclerosis and myocardial infarction), cerebrovascular disease (stroke) and peripheral vascular disease (arterial and venous  thrombosis).

It is estimated that people with hyperhomocysteinemia have about twice the normal risk of developing cardiovascular disease ​​and this condition is now recognized by the scientific community as a further risk factor in addition to other well-known cardiovascular risk factors (hypertension, diabetes mellitus, high cholesterol levels, smoking).

In addition, some evidence suggests that people with elevated homocysteine levels have twice the normal risk of developing Alzheimer's disease.

A review of the scientific researchers of the Iberoamerican Cochrane Network, aimed to evaluate the clinical efficacy of interventions designed to reduce blood homocysteine levels ​​in people with or without pre-existing cardiovascular disease, showed, for the moment, no evidence in support of homocysteine lowering ​​treatment for the prevention of cardiovascular events.

Hyperhomocysteinemia, however, remains a condition associated with an increased cardiovascular risk, and it’s considered a cardiovascular risk marker in various screening programs: it is therefore important to know what are the nutrients (vitamins and others) that help to keep under control blood homocysteine levels and whose deficiency can be associated with hyperhomocysteinemia.

Some nutrients, after European Food Safety Authority (EFSA) examination and authorization, can boast the health claim "contributes to normal homocysteine ​​metabolism".

Let's see below what they are, how they work and where they can be found (food sources).

Betaine: It originates from choline oxidation in mammals and can act as a methyl group donor in the homocysteine ​​remethylation process in the liver.

This mechanism of action supports the evidence from human studies that shows a significant lowering of blood homocysteine ​​levels after administration of betaine.

It should be remembered, however, that a daily dose of 6 g of betaine seems to lead to an increase in total blood cholesterol and LDL-cholesterol, which doesn’t occur at significantly lower doses (4 g /day). For this reason an additional warning on the label of betaine supplements is necessary.

Food sources of betaine: Quinoa, beetroot, broccoli , spinach, cereals and seafood.

Choline: It is a precursor of betaine, whose mechanism of action on homocysteine ​​metabolism is known.

For this reason, a choline-deficient diet is associated with elevated homocysteine levels ​​and studies showed an inverse correlation between dietary choline intake and blood homocysteine levels.

Food sources of choline: egg yolk, soybeans, liver, veal and turkey, lecithin.

Folic acid and folates: 5 -methyl-tetrahydrofolate is an important intermediate of folate-dependent metabolic pathway for the production of methionine from homocysteine.

Food sources of folic acid and folate: offal (kidney , liver) , green leafy vegetables ( lettuce , spinach, broccoli ), legumes and eggs.

Vitamin B12: methylcobalamin, a coenzyme form of vitamin B12 , is also involved in the methylation of homocysteine ​​to methionine, which requires as cofactors both folate and vitamin B12.

Food Sources of Vitamin B12: animal foods, especially liver.

Vitamin B6: This nutrient is essential for an alternative metabolic pathway for remethylation of homocysteine ​​to methionine (transsulfuration pathway).

Food sources of Vitamin B6: foods containing whole grain flours , some tropical fruits (avocados, bananas), hazelnuts , wheat germ, brewer's yeast and carrots, but also rice, lentils, tuna, salmon and shrimp.

In conclusion, deficiency of folate and folic acid, vitamin B12, vitamin B6, choline and betaine is the basis of an altered methylation of homocysteine​​.

Homocysteine, after an initial intracellular accumulation, is exported into the blood in amounts dependent on the severity of the deficiency as well as coexistence of genetic factors or other factors that may interfere with homocysteine metabolism.

Therefore, in the case of hyperhomocysteinemia (high blood homocysteine levels​​) it can be useful to check if there is a deficiency of some of these nutrients, which are essential to ensure a normal homocysteine ​​metabolism and to keep low homocysteine levels, preventing hyperhomocysteinemia.

Jean-Charles Fruchart et al, Atherosclerosis: Evolving Vascular Biology and Clinical Implications - New Risk Factors for Atherosclerosis and Patient Risk Assessment. Circulation, Cap. 109, 2004

Interventi per ridurre l’omocisteina per la prevenzione degli eventi cardiovascolari, www.omocisteina.net, 2013

EFSA Journal 2011

http://www.sanihelp.it/enciclopedia/scheda/8984.html

http://www.saperesalute.it/network/tuttovitamine/glossario/vitamina-b6

http://www.nih.gov/news/pr/feb2002/nia-13.htm

High Homocysteine Levels May Double Risk of Dementia, Alzheimer’s Disease, New Report Suggests

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IODINE DEFICIENCY? NOT ONLY GOITER AND MENTAL RETARDATION...

Iodine is a trace element, essential for thyroid function and for the prevention of goiter, but not only.

Iodine is fundamental for the proper development of the nervous system and iodine deficiency, in addition to being a major cause of mental retardation and neurological and cognitive deficits, is linked to an increased risk of developing  certain cancers, including thyroid cancer and breast cancer.

Iodine deficiency is widespread in developing countries , particularly in Africa , Central Asia and South- East Asia, but it is a collective interest problem even in industrialized countries . Even in Europe, in fact, there are countries "at risk" , known for being iodine deficient, including Germany , France, Belgium and Italy . In the latter it is estimated that about 6 million people (more than 10 % of the population) .suffer from goiter .

Why is Iodine so important ?

Because an insufficient intake of iodine can cause health problems in all age groups.

The clinical manifestations of iodine deficiency, or " iodine deficiency disorders " (IDD) , whose severity and symptoms are variable depending on the degree of iodine deficiency, are numerous.

While in adolescent and adult iodine deficiency is the main cause of goiter and anomalies related to the thyroid gland malfunction (hypothyroidism) , an inadequate intake of iodine in pregnant women or during breast-feeding can have very serious consequences on the health of infants and children .

Iodine deficiency in the mother and the resulting hypothyroidism can cause  irreversible neurological damage during fetal development and newborn’s growth.

The neurological damage can occur with hearing loss, learning disabilities , mental retardation and myelination disorders.

Mild iodine deficiency , such as those commonly found in Italy and Europe, can lead to minor learning disabilities and neurological problems in children.

Iodine deficiency is also considered a risk factor not only for the development of benign thyroid diseases, but even for thyroid cancer: in areas where goiter is endemic due to iodine deficiency, there is , unfortunately, an increased incidence of thyroid cancer.

Iodine deficiency is also linked to an increased incidence of benign or malignant breast tissue disorders, ranging from fibrocystic breast disease to breast cancer.

How much iodine do I need to stay healthy ?

To ensure proper thyroid function, the daily iodine requirement for adolescents and adults is 150 micrograms.

This requirement is increased in specific physiological conditions such as pregnancy and lactation, in order to ensure the normal development of the child.

Where is iodine ?

The main source of iodine for humans is diet.

In this regard, we have to highlight that the iodine content of foods is extremely variable depending on the ground in the case of foods of plant origin, depending on supply in case of foods of animal origin .

The main dietary sources of iodine are saltwater fish and shellfish, followed by eggs, milk and meat. Fruits and vegetables contain smaller iodine amounts.

But we must not forget that there are some foods , called goitrogenic foods or goitrogens , which can inhibit the absorption of dietary iodine.

Goitrogenic foods are mainly cabbage, turnips , broccoli (Brassicaceae or Cruciferae) and their goitrogenic effect is attributed to the content of isothiocyanates , molecules that bind iodine.

However, Cruciferae are not to be demonized , since they have anti-cancer properties and since their consumption in the average diet is "limited".

The average amount of iodine in the diet is insufficient to cover the daily requirement of iodine.

How can I satisfy my iodine requirements? Should I take dietary supplements of iodine?

In order to prevent iodine deficiency is sufficient to consume iodized salt (iodine –enriched salt) in place of common salt, as part of a varied and balanced diet.

Iodized salt has the same taste of common salt but provides 30 micrograms / gram of iodine (one fifth of the daily requirement for adults) , this allows an adequate iodine intake with a salt intake which don’t exceed the recommended limits .

Therefore, the intake of iodized salt is not in conflict with the reduction of salt intake to no more than 4-5 grams per day, recommended for the prevention of hypertension and cardiovascular disease.

On the health products market, dietary supplements with high amounts of iodine are available.

These, frequently algae-based, iodine supplements are marketed as slimming supplements and weight-loss aids, since iodine increases thyroid function and consequently metabolism.

These iodine supplements should always be used with caution and preferably under medical supervision. An excessive iodine intake may in fact aggravate a possible hyperthyroidism, even leading to serious consequences for your health.

I often eat at restaurants or out of home. Should I ask for iodized salt ?

Nowadays there should be no need.

We have to remember that the World Health Organization (WHO) recommends the use of iodized salt (ie enriched in iodine ) in the preparation of food with the aim of iodine deficiency disorders eradication.

So, in conclusion, in order to prevent iodine deficiency ... a little salt, but always iodized ...

Sources:

http://www.airc.it/tumori/tumore-alla-tiroide.asp

http://www.iss.it/

http://www.iss.it/osnami/

Iodine deficiency in pregnancy and the effects of maternal iodine supplementation on the offspring: a review; Michael B Zimmermann, Am J Clin Nutr 2009;89(suppl):668S–72S.

Iodine: Deficiency and Therapeutic Considerations, Lyn Patrick, ND, Alternative Medicine Review Volume 13, Number 2 2008

Iodio e Salute, Gruppo di Lavoro per l’attuazione della legge 21 marzo 2005, n.55 “Disposizioni finalizzate alla prevenzione del gozzo endemico ed altre patologie da carenza iodica” operativo presso il Ministero della Salute.

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TOO MUCH HUNGER ? TRY AN HIGH MICRONUTRIENT DENSITY DIET ! IT'S HEALTHY AND REDUCES YOUR APPETITE

Here's an extra incentive to those who, while wanting to stay in shape, struggle with an healthy diet, rich in fruit, vegetables and "high nutritional value" foods.  

A diet high in micronutrients (vitamins and minerals) reduces the feeling of hunger, one of the biggest obstacles to weight loss.

And it is the feeling of hunger , rather than the availability of food in and of itself, that drives us to eat too much, introducing more calories than needed.

The feeling of hunger is the subject of a study aimed to assess the experience and perception of hunger before and after participants shifted from their previous usual diet to a high micronutrient density diet. 

The results of this descriptive study , conducted on a sample of no less than 768 participants, who changed their eating habits moving from a diet lower in micronutrients to a diet high in micronutrients, were amazing.

The diet rich in micronutrients , after an initial adjustment phase , showed to be associated with an experience of hunger significantly different than that one experienced during the usual diet,  of lower nutritional value.

In particular, during the high micronutrients density  diet, hunger was not an unpleasant experience, it was more easily tolerated and occurred with less frequency, even skipping meals .

This kind of diet, although lower in calories, limited thus the unpleasant aspects of hunger and appetite, in other words those aspects that make it so hard to follow a weight-loss diet.

Therefore it is not simply the calorie content, but it is mainly the micronutrient density of a diet that influences what we perceive as hunger .

This interesting study, whose results should be confirmed by further studies ,shows  how a diet of high nutritional value , rich in vitamins and minerals, can be considered a sustainable eating pattern that leads to weight loss and improved health.

That said , it is important to highlight which model of micronutrients rich diet was used for this study : a diet rich in colorful vegetables, beans, seeds, nuts, fruits and whole grains and low (less than 10% of total calories) in processed foods and animal products.

Then, the five famous and almost unattainable daily portions of fruit and vegetables are welcome, considering also that is always better to prefer seasonal fruit and vegetables, fresh and possibly zero-miles , and generally unrefined  and unprocessed foods, even in our kitchen.

Sources:

Fuhrman et al. Nutrition Journal 2010, 9:51

http://www.nutritionj.com/content/9/1/51

Changing perceptions of hunger on a high nutrient density diet

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