Tomatoes: Nature's Nutritional Marvels
Tomatoes: Nature's Nutritional Marvels
Delve into tomatoes' hidden nutrients and discover their remarkable impact on overall health.
For all intents and purposes, tomatoes are known, used and relished as a vegetable. But botanists know them as berries. However you classify them, they are a genuine, undeniable superfood. Hiding in plain sight, these juice balloons' real nutrient powerhouse status flies under the radar. It’s almost certain that 99 per cent of people who eat them do so just because they are delicious and versatile, mostly blind to just how healthy they actually are. If we had any idea, we’d likely eat twice as many!
Available in some 10,000 varieties and almost as many shapes, colours and sizes, these mostly bright red flavour bombs are so heavily associated with the famous cuisine of Italy that one could be forgiven for thinking they originated there. The tip-top of the Neapolitan pyramid may be occupied more specifically by the legendary DOP San Marzano tomatoes grown in the volcanic soil surrounding Mount Vesuvius, shipped worldwide to the finest Italian restaurants overseas that would settle for nothing less.
However, those in the know are hip to the fact that tomatoes were not originally native to Europe’s boot, instead stemming from South and Central America before Spanish colonial galleons brought them back to the old world in the 16th century. Even then, they were feared poisonous by Europeans and used predominantly as ornaments for decades (or even centuries in some countries) before gaining trust and, subsequently, the immense culinary adoration we take for granted today.
A Bright Nutrient Profile
Tomatoes are rich in phytonutrients called carotenoids, such as zeaxanthin, lutein, beta carotene, and lycopene, all working together synergistically to make tomatoes the nutritional titans they are. But it is the dense concentrations of the fascinating and powerful lycopene that give tomatoes their famously eye-catching fire engine hue.
They also contain the mega antioxidant vitamin trio A, C, and E, almost every B vitamin, vitamin K, and a rich mineral profile including potassium, iron, manganese, copper, and molybdenum.
They even contain amino acids- the building blocks of protein- such as tryptophan, glutamate and aspartate. While no one typically associates tomatoes with protein, it is the exact proportion of glutamate and aspartate that gives them their unmistakable flavour profile.
Another surprising ingredient of tomatoes is fat, but it’s true: they boast mono-unsaturated fatty acids similar to those in olive oil and avocados.
Finally, tomatoes feature various types of soluble and insoluble fibres to nourish the beneficial gut bacteria strains in our small and large intestines. An intricate network of prebiotics in tomatoes, such as cellulose, hemicellulose, and pectin, promote a healthy and robust microbiome.
Cooked Tomatoes: Healthier Than Raw?
Yes! We have known for decades now that even though cooking any vegetable reduces its vitamin C content, the antioxidant activity of tomatoes actually increases after heat exposure.
Fascinatingly, a giant 2018 meta-analysis found that consumption of cooked tomatoes and tomato sauces was associated with a significant reduction in prostate cancer risk- but no such association was observed with consumption of raw tomatoes.
The explanation for the discrepancy is that the cooking process breaks apart the vegetal cell walls liberating various carotenoids (including the prostate-loving lycopene) and making them more freely available for absorption in the body. This is a beautiful example of modern science confirming the wisdom of ancient culinary traditions. So cook your tomatoes!
What is Lycopene?
This red carotenoid, also present in other red plant foods like guava, watermelon, red bell pepper, and grapefruit, is a powerful antioxidant that protects cells, LDL (the “bad” cholesterol) and DNA from free radical damage. This fantastic compound, regularly supplemented on its own, was named after the Latin word for tomato, Lycopersicon (meaning “wolf peach”), which shows its association with tomatoes above and beyond any other fruit or veggie.
Higher levels of lycopene in the blood are directly associated with significantly healthier hearts and much lower rates of cardiovascular disease. In addition to fighting cancer in the prostate, they also protect against uncontrolled cell growth in the lungs, skin, colon, and breasts.
Green tomatoes reveal by their colour that lycopene has not had a chance to develop, placing them categorically beneath mature red tomatoes for nutritional value. The same principle even holds true for fully ripe tomatoes of other hues, such as yellow and brown. Hence when selecting tomatoes at the market, you would do well to choose the most vibrantly crimson ones you can find. And as another testament to the brilliance of traditional Mediterranean diets, adding olive oil to the mix will improve lycopene absorption in the body.
Rolling Deep
While lycopene is genuinely quite something and has proven time and time again to protect against heart issues and cancer as well as cognitive decline and even osteoporosis, it’s important to bear in mind that the lycopene in tomatoes does not exist in isolation. Instead, it is nestled amid an entourage of other glorious chemical pearls, which work in tandem to achieve health-promoting effects far beyond the sum of their parts.
Science has yet to fully parse out how the complex synergistic ballet occurring between our beloved lycopene and other compounds found in tomatoes like quercetin, phytosterols, naringenin, kaempferol, and all the aforementioned vitamins and minerals promote health and prevent disease. In 100 years, we will likely know much more about the details of this collaborative impact. But we will still be eating tomatoes!
For now, it is already clear that this amazingly sophisticated combination of phytochemicals is:
Anticancer Anti-inflammatory Anti-allergenic Anti-atherogenic Antithrombotic Antidiabetic Antimicrobial Antioxidant Vasodilating Cardioprotective
So if you’re tempted to shell out for a fancy lycopene supplement, you might opt instead for Mother Nature’s own much more elegant chemical matrix.
Conventional, Organic & Canned
Conventional tomatoes are sometimes covered with wax to extend supermarket shelf-life. If they have been imported, they were likely picked green to survive transportation and artificially ripened on arrival with ethylene gas.
Canned imported tomatoes may be a bit of a double-edged sword- while the flavours of delicious Italian tomatoes may surpass anything available locally, the high acidity of tomatoes can leach lead from cheaper cans. So if heavy metals are a concern, fresh local organic tomatoes are the safest bet. Meanwhile, since canned tomatoes are pre-cooked, you will still benefit from the lycopene explosion of thermal processing, even though you didn’t cook them yourself.
Tomatoes are also commonly genetically modified, which may be another good reason to prefer organic versions, whether fresh or canned.
A Few Caveats
Tomatoes have rightfully earned their place in a healthy diet. Nevertheless, we are all unique, and some individuals have legitimate reasons for avoiding tomatoes. Here are a few reasons why tomatoes might not be right for some of us:
- Tomatoes belong to the nightshade (Solanaceae) family, just like eggplants and potatoes, and are categorically avoided by people who follow the autoimmune protocol diet (AIP) or other nightshade-reducing meal plans.
- Like all vegetables that contain tiny seeds, tomatoes are high in lectins, the sticky proteins that have the potential to bind to carbohydrates in the gut, causing digestive issues. Interestingly, the lectins are located in the skins and the seeds. So, any recipe that uses just the pulp after skinning and deseeding the tomatoes, such as traditional Italian red sauces, will completely circumvent this issue.
- Proteins in tomatoes can cross-react with latex, so those of us with latex allergies may want to be mindful of how we feel after eating them.
- They are also quite acidic. For most of us, this will go unnoticed, but for individuals with ulcers or prone to heartburn, the excess acidity (especially when combined with other acid-forming foods like lentils) can be irritating.
- Finally, the leaves of tomato plants contain toxic chemicals called alkaloids that make them inedible. So stick to the fruit!
You say tomato, I also say tomato
If you love how they taste in sauces, pastes, salads, or stews, and you love how they make you feel, then take heart in knowing that tomatoes benefit you in hundreds of different ways. Anything but simple, the manifold chemistry of the noble tomato is vastly comprehensive, featuring a staggering array of vitamins, minerals, fats, amino acids, fibres, and micronutrients like lycopene, all working together in a health-promoting symphony.
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