The wonder fruit

…known to have anti-cancerous activity

…potential to reduce stroke risk

Chidi Aja

Many people know that tomato has health benefits but how many people know that tomato has the potential to reduce stroke and more?

Indeed, tomato (Lycopersicum esculentum), a staple fruit vegetable has become an important cash and industrial crop in many parts of the world with important health benefits.

 In Nigeria, an annual total area of one million hectares is reportedly used for its cultivation while it makes up about 18 per cent of the average daily consumption of vegetables in Nigeria homes. Nigeria is ranked second largest producer of tomato in Africa and thirteenth largest in the world producing 1.701 million tonnes of tomato annually at an average of 25-30 tonnes per hectare.

Tomato is grown in many parts of Nigeria both as wet and dry season crops. Although most tomato production is on a small scale in backyard gardens, it is grown in commercial quantities in many states in the North, particularly Kano, Borno, Sokoto, Gombe, Yobe, Kaduna, Zamfara, Benue and many others.

 Nutritionists are of the opinion that fresh tomatoes are very important sources of vitamins and minerals that are essential for healthy human diet. However, study shows that organic tomatoes and smaller tomatoes are more nutritious than conventionally grown tomatoes.

This is how Joseph Mercola, an alternative physician practicing in Hoffman Estates, Illinois and author of several books, including The No-Grain Diet, and The Great Bird Flu Hoax, presents the importance of tomato.

‘Tomatoes, which are actually a fruit and not a vegetable, contain a number of valuable nutrients, and according to recent research, organically-grown tomatoes are even more nutritious than their conventionally-grown counterparts.

‘One of the most well-known nutrients in tomatoes is lycopene — the compound that gives tomato its deep red colour.

‘Lycopene is a vital anti-oxidant that has been shown to have potent anti-cancerous activity. This compound is not naturally produced in your body, so it must be supplied via your diet.

‘Other fruits and vegetables also contain lycopene, but none has the high concentration of lycopene that the tomato boasts.’

Interestingly, he submits, when cooked, the bioavailability of lycopene increases rather than decreases, as is the case with many other raw foods, as heat has a tendency to destroy valuable nutrients.

‘That said, you’re best off avoiding canned tomatoes and tomato sauces as can liners tend to contain potent estrogen mimics such as bisphenol A (BPA), which is also a toxic endocrine disrupting chemical. Your best bet is to make your own organic tomato sauce from scratch, or buy organic sauce sold in glass jars.’

Organic tomatoes have 139 per cent higher phenolic content, study shows

It seems perfectly sensible that food grown in healthier soil with natural fertilizers and no synthetic agricultural chemicals would be more nutritious. This is common knowledge among farmers, yet this age-old, common sense wisdom is greatly suppressed in the United States in order to protect the large-scale industrial farming model.

According to a recent study published in the journal PLOS One, growing tomatoes according to organic standards results in dramatically elevated phenols content, compared to tomatoes grown conventionally, using agricultural chemicals.

The researchers compared total phenol content in organic and conventional tomatoes grown in nearby plots in Brazil. This allowed for a more accurate comparison of the tomatoes, as both varieties were grown in similar soil- and climate conditions that might otherwise affect nutrient content.

According to the authors:

“This study was conducted with the objective of testing the hypothesis that tomato fruits from organic farming accumulate more nutritional compounds, such as phenolics and vitamin C as a consequence of the stressing conditions associated with farming system.”

The organic tomatoes were found to contain 55 per cent more vitamin C, and 139 per cent more total phenolic content at the stage of commercial maturity, compared to the conventionally-grown tomatoes. According to the authors:

“[T]his seems consistent with the more than two times higher activity of phenylalanine ammonia lyase (PAL) we observed throughout fruit development in fruits from organic farming.

Taken together, our observations suggest that tomato fruits from organic farming experienced stressing conditions that resulted in oxidative stress and the accumulation of higher concentrations of soluble solids as sugars and other compounds contributing to fruit nutritional quality such as vitamin C and phenolic compounds.”

The health benefits of tomatoes

Tomatoes are rich in flavonoids and other phytochemicals that have anticarcinogenic properties. They’re also an excellent source of lutein, zeaxanthin, vitamin C, which is most concentrated in the jelly-like substance that surrounds the seeds, as well as vitamins A, E and B-complex vitamins, potassium, manganese and phosphorus. Other lesser known phytonutrients found in tomatoes include:

 •Flavonols: rutin, kaempferol, quercetin

•Flavonones: naringenin, chalconaringenin

•Hydroxycinnamic acids: caffeic acid, ferulic acid, coumaric acid

•Glycosides: esculeoside A

•Fatty acid derivatives:-oxo-octadecadienoic acid

 Getting back to lycopene — a carotenoid antioxidant that gives fruits and vegetables like tomatoes and watermelon a pink or red colour — this is one nutrient you’ll want to be sure you're getting enough of.

Lycopene's antioxidant activity has long been suggested to be more powerful than other carotenoids such as beta-carotene, and recent research revealed it may significantly reduce your stroke risk (while other antioxidants did not). The 2012 analysis followed over 1,000 men in their mid-40s to mid-50s for more than 12 years.

After controlling for other stroke risk factors, such as older age and diabetes, they found that men with the highest blood levels of lycopene were 55 per cent less likely to have a stroke than those with the lowest. Other antioxidants, including alpha carotene, beta-carotene, alpha tocopherol (vitamin E) and retinol (vitamin A), showed no such benefit.

The high blood levels of lycopene were said to be a marker for intake of tomatoes and tomato-based products, as these are a particularly concentrated source. It's estimated that 85 per cent of dietary lycopene in North Americans comes from tomato products such as tomato juice or tomato paste. In addition to lowering your risk of stroke, lycopene from tomatoes (including unsweetened organic tomato sauce) has also been shown to be helpful in treating prostate cancer.

Tomatoes must be eaten with fat for proper absorption, and two other caveats

 Lycopene is a fat-soluble nutrient, which means eating it with some dietary fat is essential in order for it to be properly absorbed. So a slow-cooked tomato sauce that contains olive oil or another source of healthy fat, such as grass-fed beef, may be an ideal source.

One caveat: when making your tomato sauce, start out with fresh tomatoes, as canned tomatoes typically have a lining that contains bisphenol-A (BPA) which is a potent estrogen mimic that have been linked to a number of health problems, including diabetes, heart disease, heightened risk of breast and prostate cancers, neurological effects, reproductive problems and obesity.

The current US federal guidelines put the daily upper limit of “safe” exposure at 50 micrograms of BPA per kilogram of body weight. According to endocrinologist Dr. Fredrick vom Saal, a tin can contains around 50 mcg of Bisphenol A (BPA), and when the cans contain acidic food such as tomatoes, it will leach more BPA from the liner into the food. According to Consumer Reports’ testing, just a couple of servings of canned food can exceed the safety limits for daily BPA exposure for children.

So, ideally avoid canned foods entirely and stick to fresh fruits and vegetables, or switch over to brands that use glass containers instead. One other point: if you eat a lot of ketchup, you might want to consider choosing an organic version (as well as one that is unsweetened, as regular ketchup is a common source of sugar and high fructose corn syrup). Organic ketchup has been found to contain 57 per cent more lycopene than conventional national brands.

 Cooked tomatoes may be better than raw

Tomatoes differ from many other raw foods in that cooking them may in fact be better than eating them raw. Research shows that cooked tomatoes (such as in tomato sauce or tomato paste) not only increases the lycopene content that can be absorbed by your body, but also increases the total antioxidant activity. In one study, when tomatoes were heated to just over 190 degrees F (88 degrees C) for two minutes, 15 minutes and 30 minutes:

•Beneficial trans-lycopene content increased by 54 per cent, 171 per cent and 164 percent, respectively

•Levels of cis -lycopene (which is a form easily absorbed by your body) rose by 6, 17 and 35 per         cent, respectively

•Overall antioxidant levels increased by 28, 34 and 62 per cent, respectively

As for tomatoes, they’re one of the most potent sources of lycopene, shown to have anti-cancerous activity and the potential to reduce stroke risk. Just remember to consume your tomatoes, whether raw or cooked, with some type of fat, such as olive oil, since lycopene is a fat-soluble nutrient. Also remember to choose organic varieties, whether whole tomatoes or tomato paste, ketchup or sauce, and avoid anything that comes in a can, since the acidity of the tomatoes will increase toxic BPA release from the liner in the can.

Despite the huge advantage, Nigeria has in tomato production, the country imports 65,809 tons of processed tomato valued at N11.7 billion ($77.167 million) annually. This is because not less than 50 per cent of the tomato produced in the country is lost due to lack of preservation. According to World Food Science, about 30-50 per cent of perishable produce are lost after harvest due to poor storage system and humid weather condition exacerbated by poor marketing distribution and access to markets.

Industry experts posit that there is no clear cut policy presently that addresses the problem of post-harvest losses in Nigeria despite the problem having lingered in the country for as long as agriculture exists. More pathetic, they maintain, is the fact that most Nigerian farmers have not been able to upgrade their farming methods to adapt to improved technologies that would encourage higher yield and less effort in terms of use of energy to farm.

Accordingly, they recommend the following policy actions to reduce post-harvest losses:

. Provision of good storage facilities to store the produce that are harvested before being taken to the market in order to reduce losses that occur at the farm level;

. Training initiatives on post-harvest handling of perishable products such as tomato and periodic follow ups, feedback and adoption measurement for sustainability;

. Improvement in roads linking farms to market to reduce transit losses;

. Establishment of farmers market and cooperative marketing to reduce losses related to marketing functions.