Home-grown tomatoes - delicious and healthy
As popular as tomatoes are in many countries today, they were not introduced into the kitchens of Europe and Latin America until the middle of the 19th century, before they were considered poisonous and used only as ornamental plants. Today tomatoes are one of the most important suppliers of nutrients and vitamins in Western nutrition.
Lycopene: inhibits cancer and protects against cardiovascular diseases
One of the most important ingredients of the tomato is lycopene, a carotenoid that acts as a pigment to give it its red colour. Lycopene is a particularly powerful antioxidant and responsible for the cancer-inhibiting effect of tomatoes. In particular, the effect of lycopene on prostate cancer has been scientifically investigated.
The lycopene content in cooked tomato products is particularly higher than in fresh tomatoes. Concentrated tomato paste, for example, contains up to 60 mg/100g lycopene, the raw tomato only 3-5 mg/100g. Dr. Richard Béliveau and Dr. Denis Gingras conclude in their book "Foods to fight cancer" (2007) that eating two meals a week with tomato sauce can reduce the risk of developing prostate cancer by 25 percent. However, there is still no clear link and further research is needed (Xu et al 2016).
Lycopene also inhibits blood coagulation and thus probably protects against cardiovascular diseases such as strokes and heart attacks. According to a Finnish study (Karppi et al 2012), men with the highest blood lycopene content had a 55 percent lower risk of stroke than those with the lowest lycopene level. However, it is objectionable that lycopene in this study could also only be a marker for a certain dietary style and not necessarily the protective factor itself.
Low in calories and rich in nutrients
But lycopene is not the tomato`s only effective nutrient and perhaps its special cocktail of minerals and vitamins is what makes it so particularly healthy. With a low calorie content (17 kcal), 100g of raw tomatoes contain a lot of vitamin C (124 mg), A, B1, B2, B6, E and folic acid, as well as numerous minerals (potassium, phosphorus, magnesium and iron) and secondary plant substances (besides lycopene flavinoids, phenolic acid, terpenes).
Of course, tomatoes from your own garden or from the balcony are best. Freshly picked and fully ripened, they not only contain the most bioactive nutrients, but also taste best. You can choose from over 2,500 cultivated varieties.
How can the health-promoting effect of tomatoes be used optimally?
- Eat the ripest and most intensively coloured fruits. They have the highest content of health-promoting substances.
- The highest lycopene content is achieved by heating, as the cell walls are broken down and the lycopene is more readily available to the body.
- The absorption of lycopene by the body is facilitated by the addition of fats (e.g. olive oil).
Tips for the correct storage of tomatoes:
- When stored in the refrigerator, tomatoes lose colour and taste, they are best stored at room temperature. In this way they retain their nutrients and can develop their full aroma.
- Tomatoes that are not yet fully ripe further ripen in the sunlight, or if you place apples next to them (they release the ripening gas ethylene).
- Conversely, tomatoes allow other ripe vegetables to ripen further, such as cucumbers. As these then become soft, cucumbers should not be stored together with tomatoes.
- It is best to eat fresh tomatoes within five days, after then they lose their nutrients.
References:
Béliveau, R. & Gingras, D. (2007): Foods to fight cancer. London.
Karppi, J., Laukkanen,, J.A., Sivenius, J., Ronkainen, K. & Kurl, S. (2012): Serum lycopene decreases the risk of stroke in men - A population-based follow-up study. Neurology79 (15): 1540 - 1547.
Xu, X. et al. (2016): Tomato consumption and prostate cancer risk: a systematic review and meta-analysis.. Sci Rep.. 6, (37091): 1-8.