It is important that women of reproductive age make sure that they are getting enough folate when planning to have a baby, and during pregnancy. The type of folate/folic acid, and the correct usage in terms of timing and doses required is also important.

  Folate is essential for cell division, the development of the spinal cord and the growth of the baby during pregnancy. There is also evidence to support that its consumption after birth benefits as it improves the composition of breast milk and helping to support further infant growth and development. Maternal folate deficiency is associated with fetal congenital malformation. Neural tube defects (NTDs) mainly anencephaly and spina bifida are the most common. In mother, folate deficiency can limit the production of red blood cells leading to megaloblastic anaemia, which is characterised by large immature red blood cells in the peripheral smear.

What is the difference between folate and folic acid?

Folate and folic acid are both forms of the water soluble vitamin B. Folate is the naturally occurring form of the vitamin found in a number of foods, especially vegetables, while folic acid is the synthetic form of the vitamin, and it is used for the fortification of foods (e.g. pasta, cereals, and bread )and the manufacture of supplements.

Food sources of folate

 As shown in figure 1, folate is found in a range of foods including leafy vegetables, pulses, and fruits. When consuming folate it is important to consider some factors such as cooking methods, and  bioavailability.

 Cooking methods can lead to nutrient losses for instance, 100g raw lentils contain 110μg folate, compared with 30μg in a similar proportion of food after cooking. Considering that folate is a soluble vitamin, thus dissolves in water, it is preferable to steam the vegetables rather than boil them.

Figure 1:Natural food sources of folate 

The term bioavailability is used to describe the rate to which a nutrient is more actively absorbed and becomes available in the body. In terms of folate, its bioavailability tend to be low with only about 10 per cent being absorbed by the body, particularly by the time food has been stored, prepared, and cooked. In contrast, the bioavailability of folic acid is much higher with about 90 per cent ingested and being absorbed by the body. Because of its high bioavailability, in 2007, the Food Standards Agency in the UK recommended that folic acid should be added compulsorily to either bread or flour.

Dietary recommendations

It is advised that in addition to dietary sources 0.4mg/day folic acid should be taken from supplement sources. While this is a general recommendation, the ranges of folic acid supplementation vary across Europe from 0.2mg-0.6mg per day, thus is it important to advise your doctor. For all women, folic acid should be taken one month before and at least 12 weeks after conception. In some instances, it may take up to three months to achieve an optimal red blood cell folate level, depending of the folate status in the body when conception occurs and the dose of folic acid taken.

Evidence supports that some women should have higher folate/folic acid requirements than of those of the general population. Women who have had a previous pregnancy affected by a neural-tube defect, women with diabetes, and women with a Body Mass Index of 25kg/m² or more, should take 5mg folic acid daily starting at least one month before conception.

Can folate be harmful if taken on excess?

Women cannot get too much folic acid from foods containing naturally folate. However, when taking folic acid tablets, it is important to be careful on the frequency and the dose of folic acid. Women should not consume more than the recommended amount of folic acid, unless recommended by their health professional. Taking large amounts of folic acid might hide a vitamin B₁₂ deficiency. Although increased folic acid consumption can correct anaemia associated with vitamin B₁₂ deficiency, it cannot correct the changes in the nervous system that result from B₁₂  deficiency which can lead to brain and nerve damage.

In summary,

It is important that women who are planning to become pregnant aim to eat a folate-rich diet, while topping this up with appropriate supplement sources. Supplements should be taken on a daily basis for at least one month before pregnancy and the first 12 weeks once pregnant. Finally, it is important to remember that not all women have the same folate requirements, with women having previous pregnancies with neural-tube defects, obese or diabetes needing higher levels.

References

Betti, C., Fekete, K., Dullemeijer, C., Trovato, M., Souverien, O.W, Cavelaars, A., Dhonukshe-Rutten, R., Massari, T., and Cetin, I. 2012. Folate Intake and Markers of Folate Status in Women of Reproductive Age, Pregnant and Lactating Women. Journal of Nutrition and Metabolism.

Hoyo, C., Murtha, A.P., Schildjraut, J.M., Forman, M.R., Calingaert, B., Demark-Wahnefried, W., Kurtzberg, J., Jirtle, R.L. and Murphy, S.K. 2011. Folic acid supplementation before and during pregnancy in the Newborn Epigenetics Study (NEST). Journal of Public Health. Vol. 11, np. 46

Nulty H.M. and Scott,l.M.,2008. Intake and status of folate and related B-vitamins: considerations and challenges in achieving optimal status. British Journal of Nutrition, vol. 99, no. 3, pp. S48–S54

Talaulikar, V. and Arulkumaran, S., 2011. Folic acid in pregnancy. Available from : http://ac.els-cdn.com/S1751721411000261/1-s2.0-S1751721411000261-main.pdf?_tid=a1456c2c-f6db-11e3-a2a7-00000aab0f01&acdnat=1403091071_014e55777c561cdefc6298e184262385

Food Standards Agency. Board Recommends mandatory fortification. May 2007. Available from <http://webarchive.nationalarchives.gov.uk/20120206100416/http://food.gov.uk/news/newsarchive/2007/may/folatefort>

Daly LE, Kirke PN, Molloy A, Weir DG, Scott JM. Folate levels and neural tube defects. Implications for prevention. JAMA 1995; 274: 1698e702

Although sugar is an inseparable part of the food we consume increased consumption of more than 10% of the total daily energy has been associated with dental carries and obesity. Nowadays, due to the increased incidence of obesity and diabetes, consumers and food manufacturers have an interest in the increased availability of foods with reduced caloric content by the use of artificial sweeteners which by definition are food additives that duplicate the effect of sugar in taste, containing less calories.

Stevia is derived from stevia rebaudiana Bertoni, a South American plant which has been used for centuries to sweeten herbal teas and other beverages. Stevia contains natural sweeteners, called steviol glycosides which contain stevioside and/or rebaudioside A as the principal sweetening components. It is important to highlight that steviol glycosides are low-calorie, high-intensity sweeteners which taste up to 300 times sweeter than sugar. In 1991, stevia import to the U.S. was banned by the Food and Drug Administration who claimed it as ‘unsafe food additive’. It remained banned until 1994 when it was approved as a dietary supplement. By 2010, sweeteners derived from stevia were permitted in several countries including China, Japan, South Korea, Mexixo, Austalia, New Zeeland, France, and Hong Kong and in 2011, the use of stevia was also approved by the European Union. The Joint FAO/WHO Expert Committee on Food Additives (JECFA) has established an acceptable daily intake of 0-4mg/kg body weight expressed as steviol which is equivalent to 12mg/kg body weight as rebaudioside A or 720mg for a 60kg woman or 840 for a 70kg man.

Steviol glycosides allow consumers to enjoy sweet taste without adding to the daily energy intake as they do not contain significant calories, thus may have the potential to play a role in the prevention and management of overweight and obesity. It is interesting to note that those with a rare genetic disease known as phenylketonuria can freely consume stevia as this sweetener is phenylalanine-free compared to other sweeteners like aspartame.

Studies looking on the effect of stevia consumption on blood pressure and blood glucose have shown that neither blood pressure nor blood glucose were affected making the conclusion that steviol glycosides are safe for use by individuals with heart disease and diabetes.

While the use of stevia was judged in the past due to its toxic effects, the most recent studies have shown that stevioside and rebaudioside A are not toxic nor carcinogenic.

Is stevia safe for everyone?

Although there is little evidence to date, some sub-groups of the population should avoid the consumption of stevia including children with atopic eczema and individuals suffering from auto-immune diseases or inflammation of the gastrointestinal tract. More research need to be done to draw better conclusions in these sub-groups of the population, however individuals with the above characteristics should discuss the use of stevia prior consumption.

The use of stevia sweeteners...

Stevia sweeteners are widely used by food companies and they are proposed to be used in a variety of foods and beverages like tea, coffee, soft drinks, tinned fruit and jams, ice-creams, cakes and alcoholic drinks.

Where can I get stevia?

Stevia sugar can be purchased at health food stores, natural product shops, pharmacists, and online.

How to use stevia?

Because stevia could be 300 sweeter than sugar attention should be given to the amount used so it is important to refer to the manufacturer’s instructions. As a guide, one tablespoon of sugar is equivalent to 1 and ¼ of teaspoons, and one teaspoon of sugar is about 3/8 teaspoon of stevia powder. Stevia can also be used in baking as stevia is stable at high temperatures.  Stevia has been shown to maintain a good stability for 2 hour up to 130 ºC but in higher than 140 ºC for  a prolong time it can loose its stability.

Θεωρείται ένα πολίτιμο τρόφιμο το οποίο λατρεύτηκε από τους Αρχαίους Αιγυπτίους, Έλληνες, και Ρωμαίους. Στη χώρα μας, το σπαράγγι είναι αυτοφυές, αλλά καλλιεργείται κιόλας, λόγω της υψηλής σε περιεκτικότητας θρεπτικών συστατικών. Υπάρχουν τρία είδη καλλιεργημένου σπαραγγιού: πράσινα, λευκά και μοβ. Τα πράσινα σπαράγγια οφείλουν το χρώμα τους στην χλωροφύλλη που συντίθετα με την έκθεση του στον ήλιο. Τα άσπρα σπαράγγια σκεπάζονται με χώμα ώστε να διατηρούν το άσπρο τους χρώμα και τα μοβ οφείλουν τον χρωματισμό τους στον ήλιο. Το σπαράγγι είναι ένα τρόφιμο προικισμένο καθώς έχει διαιτητικές και ιδιαίτερα διουρητικές ιδιότητες. Επιπλέον,  το σπαράγγι αναγνωρίζεται για τις φαρμακευτικές του ιδιότητες λόγω του ότι περιέχει ασπαραγίνη. Η θερμιδική αξία του σπαραγγιού θεωρείται χαμηλή και είναι 26 θερμίδες/100 γραμμάρια σπαραγγιού. Είναι πολύ καλή πηγή φυτικών ινών και αποτελεί εξαιρετική πηγή βιταμίνης Κ, βιταμίνης Α, βιταμίνης C ,φυλικκού οξέος, ριβοφλαβίνης, θειαμίνης, νιασίνης καθώς και σεληνίου, σιδήρου, φωσφόρου, καλίου,  μαγγανίου και χαλκού.

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