Phytochemical foods

Phytochemical foods are those vital plant substances that help to keep us healthy by reducing oxidative stress and chronic inflammation.

They have a chemical structure known as a polyphenol; there are hundreds of them and you certainly can't and shouldn't try to track whether you've had enough resveratrol or lignans today; it would drive you crazy.

This page was updated on 7th November, 2018.

By Bernard Preston

These are a broad spectrum of plant substances found in virtually all fruits and vegetables, and the oil rich seeds like flax, and in the olive. Your authentic hummus recipe is particularly full of them.

Each of these compounds has its merits, but their particular function in health is often unproven and open to speculation; yet despite their unsubstantiated status at this time, we ignore them at our peril.

It certainly does take a little extra time each day to drop a soaked prune into your muesli, grind some flax seeds and to squeeze your own orange juice. It's either that or spend a great deal more visiting and paying your doctor; it's your choice.

Our theme at this site is making the healthy stuff fast; perhaps an extra half an hour each day should be sufficient. Less television would do us no harm, in any case.

These are some of them; they are terms that you may have heard, but likely only vaguely. They are the substances that give onions their particular eye watering smells, the aphrodisiac in parsley, the bright green cancer preventing colour in broccoli, yellows in butternut and the purple pigment in mulberries; and hundreds upon thousands of others.

Phyto meaning of plant origin, of course, plus a naturally found organic chemical brings this relatively new term to the literature; but we are very familiar with them. We smell and see, and consume them every day; your taste buds love them.

It is the phytochemicals in foods that underpin the strongly believed opinion that we ought to be eating a minimum of five coloured foods every day, and preferably ten. That's if we want to greatly reduce our risk of getting cancer and dying of heart disease or a stroke.

Phytochemical Foods

Phytochemical foods explains how they work and why the black and white diet is so deadly. There are over 1000 of them; it would take a book to cover them properly, and new research is coming out almost daily.


Lignans and isoflavonoids are estrogen-like substances found in flax and sesame seed, whole grains and legumes like tofu and chickpeas; they are rich phytochemical foods. 

Just five minutes to make the healthiest, lightest, tastiest whole grain bread: Panera bread menu recipe ...

In the colon, lignans and isoflavonoids are broken down by bacteria into substances that are now known to protect against breast cancer for example.

They are not found in flaxseed oil, even "lignan enriched" flaxseed oil has much less than in the whole seed.

Hummus, being made from chickpeas, tahini and parsley is a balanced all-round phytochemical foods. Make it yourself, in four minutes, in your own home. Authentic hummus recipe.


Flavonoids are powerful antioxidants, protecting our cells and enabling the body to mop up the free radicals that cause cancer. They give our fruits, salads and vegetables their bright colours.

Flavonoids are important in the management of our cholesterol, blocking absorption of the bad LDL and increasing the healthy HDL. It's those good high density lipoproteins that mop up the stuff that clogs our arteries, decreasing plaque and returning it to the liver for degradation.  

Flavonoids are found in fruits like grapes, the berry family, and it comes as no surprise that the fruit of an apple a day fame is full of flavonoids; teas, tofu, broccoli, parsley, the garlic and onion family and red wine too.

Delicious foods and we should all be indulging ourselves daily in at least of four of these treats; feast on them.

Another group of polyphenols are called stilbenes, the most famous of which is resveratrol (1); it's found in many berries, grapes, red wine, and avocados, for example. It's known for its powerful anti-inflammatory effects.

The protection afforded by fruits and vegetables have been clearly shown to lower inflammatory markers such as CRP, and plasma levels of plasma homocysteine. (2)

What are phytosterols

and stanols?

These are phytochemical foods found in oils of plant origin. They have cholesterol-like properties, and thus compete with cholesterol of animal origin at the absorption sites in the alimentary canal.

They also affect some of the inflammatory markers positively.

Avocados, extra virgin olive oil and whole grains and nuts are the best sources of stanols and sterols.

"Some studies suggest taking 1.5 to 3 grams of phytosterols/-stanols in frequent small doses daily may reduce total cholesterol levels by up to 17%. There are also suggestions that in addition it may protect against cancer."

Dr Jenny Jamieson, MD.

Drug and food companies have been quick to produce drugs and  "enriched" margarine but the taste is not great. Food synergy suggests rather eating whole grain breads, avocados and copious dribblings of olive oil on green salads.


These are a very large group of phytochemical foods. Subgroups are:

  • Carotenoids
  • Saponins
  • Indoles and glucosinolates
  • Fatty acids like those in almonds and sesame seeds, the beta-sitosterol in avos, vitamin E and the omegas.

The only way to be getting adequate amounts of them is to be regularly eating from a wide range of foods. The "black and white" diet is deadly. Like TV, turn to colour!


Carotenoids  are also strong antioxidants. These are the colourful oranges and yellows in pumpkins and citrus, the red in an tomato and strawberry and the deep dark green of spinach, broccoli and kale benefits, the purple in mulberries and beets. There are at least twenty different carotenoids in lemons and oranges, for example, the perfect phytochemical foods. But the power of purple foods takes a lot of beating too. 

Free range cage free eggs have seven times the carotenoids because of their ready access to greens; they are also the best source of choline. Our hens can also indulge in the fruit from the question what is a worm farm?

Carotenoids are the reason that strawberries protect the eyes from cataracts and macular degeneration. Carotenoids are the reason that tomatoes protect the prostate gland. Enjoy them in hot buttered gem squash and butternut squash soup recipes

In particular two carotenoids, lutein and zeaxanthin give vital protection against damaging high frequency light entering the eyes; lutein macular degeneration tells the story of five million needlessly blind Americans. Kale is the richest source.

Lycopene is the red colour in tomatoes; cooked or raw, it gives those who enjoy a tomato a day 50% protection against prostate cancer. Read more at tomato prostate.

Free range hens into their greens; spinach, beets, wild cabbage and kale to name a few. Keep a few, or be prepared to pay a lot more for their eggs.


Certain deadly enzymes in the gut that may cause cancer are deactivated by saponins. They are found in whole grains, many salads, fruits and legumes, and are particularly high in asparagus. And in red wine, tea, both black and green.

Indoles and Isothiocynates

These phytochemical foods contain a very powerful antioxidant sulphur-containing substance called indole-3-carbinol.

The name's not important; known as I3C this is the substance that makes broccoli the queen of the anti cancer foods. It's found in lesser quantities in cauliflower and cabbage, kale and I would think lettuce too. Another important isothiocynate in broccoli is glucoraphanin; enjoy a  delicious soup recipe at broccoli facts.


Xanthophylls are the yellow pigments found in many foods such as peppers, citrus, pumpkins, corn and egg yolks; they are also found in many dark green leafy vegetables like kale and spinach.

Two particularly important xanthophylls are lutein and zeaxanthin which are found in very high concentrations in the retina of the eye; a deficiency is the prime cause of age onset macular degeneration, the most common cause of blindness in the elderly.

Read more at zeaxanthin macular degeneration and lutein benefit.

They are both found together in zucchini squash.

The more varied diet of a free range hens gives higher natural xanthophylls, but the synthetic forms are added to commercial feeds. It's not difficult to distinguish the free range egg from our own hens.


Allicin is another member of the phytochemical foods; it's found in the onion family, and especially garlic. Garlic is another powerful antioxidant.

It remains controversial, as some research indicates that cholesterol levels are not affected by garlic in any form, whilst other research suggests it does indeed decrease LDL cholesterol.  

Whilst it may not decrease cholesterol absorption from the gut it's been proved to decrease cholesterol production in your body. For many years garlic has been used to treat colds and to fight infections too. Read more about allicin benefits.

If you want your own allicin from the garden then take a look at growing leeks.


Oleocanthal is a phytochemical food found in unprocessed olive oil; for the record it's a phenylethanoid, but forget that. It acts as a low level anti-inflammatory, working in the same way as the Cox inhibitors but without the serious side effects.

It is responsible for the burn in the back of the throat in a good extra virgin olive oil, and is removed by processing to produce the refined olive oils.

Oleocanthal gives those enjoying the Mediterranean diet protection against heart disease and Alzheimer's for example and researchers in France have found that it also along with lutein and zeaxanthin protects against macular degeneration.


Choline is now considered to be one of the B vitamins, so essential is it, but it's yet to be numbered, so we'll include it as one of our phytochemical foods.

In humans it's a part of a vital neurotransmitter called acetylcholine and in plants in cell walls.

It cannot be synthesised in our bodies and we must consume it daily; the average Western diet has at best half the recommended daily allowance. Choline food sources is an important subject for us all; a deficiency is the cause of many diseases, including spinal cord defects in the newborn; there's at least one in most Western schools due to poor nutrition; they remain semi-paralysed for life. 

Essential oils

Essential oils have long been known for their antimicrobial and antifungal activities, and there's heaps of scientific evidence that this is fact. They contain many different phytochemicals, and I mention only two that have been shown to be highly effective against various mould spores found on food.

They are citral and eugenol; the former found in citrus obviously, and the latter in basil and cloves. 

The importance of these phytochemicals is the prevention of food going off so quickly; many of these fungi also produce high toxic metabolites known in general as mycotoxins.

You may have heard for example of aflatoxin produced by Aspergillus flavus in peanuts and many staples such as corn and sunflower seeds; it causes stunted growth in children and liver cancer.

If you're interested, then read more at inhibitory action of some essential oils and phytochemicals on the growth of various moulds isolated from foods.

Broccoli soup

Broccoli soup remains one of the great favourites in Bernard Preston's home; she who must be obeyed made it yesterday for supper. It's loaded with many of these phytochemical foods, including folate and choline.

Chickpea burgers

So the family loves burgers. Mine do too, and so do I. But with all the evidence coming out about a high red-meat diet, a vegetable burger should be an option. The problem is that most veggie-burgers are made from soya-beans. And I for one HATE soyabean burgers. But these chickpea burgers are delic, rich in our phytochemical foods.

To sum up

Please, please don't start on a not uncommon journey that I call the health nut neurosis.  It makes no sense to every day start asking yourself: have I had my indoles? What about the terpenes, have I had enough of them? Ooh, I forgot about my lignans today.

Work rather in broad principles, and relax;

  • Whole grain breads and brown rice
  • An assortment of coloured fruits
  • As many bright salads and vegetables as possible.
  • Healthy fats, particularly from the olive, avocado, flaxseed and fish like salmon and pilchards.
  • Throw in some legumes like green beans and peas, garbanzos and lentils.

Follow those principles and you will have more than enough of your phytochemical foods. As a bonus, you can kiss constipation goodbye, you'll be getting plenty of the vitamins and minerals your body needs, and you'll be on a low inflammation diet; less arthritis, blood vessel disease, and the best protection possible against cancer. Your cholesterol doctor will be beaming and the drug companies scowling.

Is it worth an hour a day to prepare slow foods, most of them made fast? You decide.

It comes as no surprise that the proven most effective remedy against stubborn constipation is full of phytochemicals.

Grandmother's solution is the prune, of course. It's more effective than the most frequently prescribed medication from your doctor; cheaper too.

Foods that lower cholesterol

Many of these phytochemical foods have proven cholesterol-lowering properties.


Constipation is a serious problem in today's society, provoking a host of serious large bowel and rectal diseases. Whilst phytochemical foods per se only contribute in part, they are found in those fruits and vegetables that are high in fibre.

Ask anybody enjoying a large amount of phytochemical foods, and you'll find they have no problems with constipation. Beetroot constipation is a favourite page, in part to the phytochemicals called betalains.

Useful links

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