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What are Phytonutrients
What are Phytonutrients?
Phytonutrients ("phyto" means plant) are biologically active compounds in plants.
To date, scientists have identified over 12,000 phytonutrients. One plant can contain literally hundreds of different types of these compounds.
Phytonutrients define a plant's color and flavor.
They're absolutely vital for a plants' health and survival.
Because phytonutrients help plant growth by deterring harmful predators, bacteria, and viruses.
They also protect against damaging sun rays, protecting our general health.
The phytonutrients in plants take on a new life when we eat them.
They work to benefit our health and longevity. Dietitians and nutritionists are clear that eating a balanced diet rich in plant foods will help reduce the risk of long-term diseases such as heart disease, stroke, cancer, and cataracts.
High doses of a number of phytonutrients have pharmacological effects in the body, and even today, plants remain important sources of a range of therapeutic drugs.
Phytonutrients are the active "ingredients" in herbal medicines, too.
How are phytonutrients different from Vitamins?
Vitamins, minerals, protein, fat, carbohydrate, and fiber are all essential nutients, meaning we must get them from food in order for out bodies to function properly.
For example, if we lack vitamin C in our diet we develop a deficiency disease call scurvy which could ultimately lead to death.
Phytonutrients are different from these more familiar food components and are not technically not "nutrients." Instead, they are classified as "non-nutrient" compounds - only because there is no clear in the-lab evidence they're "essential to life." For this reason, there is no clearly defined recommended intake for different phytonutrients (except for
the standard 5 fruits and vegetables a day") in the same way that vitamins, minerals, and other nutrients have RDA's.
However, this could all change as research into phytonutrients progresses.
Researching Plant Foods
For decades, plant scientists have been researching phytonutrients in relation to the health benefits plants can give.
In 1981, the first report linking diet and cancer was published by two British professors, Sir Richard Doll and Richard Peto. They suggested that 35 percent of all cancers could be caused by diet.
This stimulated interest in the role of plant foods in human health. Only in the last ten years has phytochemical research taken off.
Compare this to over a century of research into nutrient.
Important plublications then triggered a growing fascination with phtochemicals.
Between 1982 and 1992 a number of epidemiological reviews (studies which identify, and seek to explain the incidence of health and disease in a population.
Both across Europe and the U.S, it was concluded that diet could influence many cancers, and that high fruit and vegetable intakes were linked to decreased risk.
Then in 1993 came a report from the Zutphen Elderly Study, a study of the health and dietary habits of 800 elderly Dutchmen.
After five years, those with the highest intakes of fruit and vegetables containing phytonutrients called "flavonoids" had a significantly lower risk of dying from coronary heart disease compared to those with
low intakes.
This was true even after accounting for other factors that can effect health, namely age, weight, cigarette smoking, blood pressure, blood cholesterol, activity level, and intakes of vitamins C and E, betacarotene, and fiber.
Phytochemical research is now flourishing.
Until recently, much research centered on the effects of pure phytonutrients in a laboratory environment.
Now the focus is on how phytonutrients react in the body, and the search is on for new, beneficial phytonutrients.
This will add weight to the existing findings of population and laboratory studies.
It will also provide clearer information about optimal food intakes, and in what forms and combinations so we can make the most of plant power.
THE CHANGING DIETARY PATTERNS OVER TIME
"Diets in developed countries have changed dramatically over the course of time. Some of the most rapid change has been in the last 50 years, resulting in a wide range of refined foods, and lower intakes of plant foods.
The change in the human diet has resulted in a shift from what was an unrefined, low fat, plant food-rich diet to a highly refined diet that's instantly accessible, and often lacking in fruit and vegetables.
ANCESTRAL DIETS
For tens of thousands of years the diet of our hunter-gatherer ancesotors was made up of varying proportions of plant foods - root vegetables, leaves, seeds, fruits - and animal foods.
Although the food supply wasn't always reliable, their diet would have been rich in nutrients such as folate, vitamin C, omega 3 fats - and phytonutrients.
In evolutionary terms, we should still be genetically adapted to a diet brimming with diverst plant foods and phytonutrients; the type of diet that seems to allow our body to function at it's best. Yet the start of food cultivation and processing marked the beginning of a decline in the variety and quantity of plant foods in human diets.
CULTIVATED CROPS
Farming arrived about 10,000 years ago with the cultivation of crops and a more reliable food supply; whet, maize, and rice became staple crops in different parts of the world.
During the late nineteenth century, food processing, preservation, and transportation developed, together with improvements in breeding techniques for plant foods and live-stock.
Unleashed, these agricultural and technological advances surged full stem ahead.
Since the 1950's, home freezers, microwave ovens, convenience food, one-stop supermarkets, restaurants, and home delivery services have all made their mark.
On one hand, we have never had such a variety of foods; on the other, the Western diet is more refined than ever before. We're far less active too.
These diet-treated problems are not new to developed countries.
As technology and convenience food enters developing countries, and local people move away from their traditional diets, problems inevitably follow.
NUTRITIONAL RESEARCH
Nutritional research in the 1930's and '40's focused on vitamins, minerals, and general nutrient requirements.
This formed the basis for the "four food groups." Dietary balance was promoted, and worldwide health problems caused by nutrient deficiencies were addressed.
In the late 1950's, Dr. Ancel Keys began a major study - the Seven Countries Study - to investigate the diet and pattern of disease in 12,000 middle-aged men in Greece, Italy, former Yugoslavia, the Netherlands, Finland, the U.S., and Japan.
The findings showed that what we eat can effect our long-term health and highlighted the health benefits of the Mediterranean and Japanese diets.
A whole new interest in diet and health was born and dietary trends took hold: vegetarianism in the 1960's; intensive farming and convenience food in the '70s; "eat lest fat and more fiber" in the 80s;
optimal health and "wellness" as a focus in the '90's.
Meanwhile, chronic health conditions - such as diabetes, obesity, cancer, osteoporosis, arthritis, and postmenopausal symptoms - have all been on the increase.
Thanks largely to modern medicine, sanitation, and enough food to eat, we live longer than ever before.
But our quality of life now is affected by health much too often.
It could be our changing diet and lifestyle has reached a point where life expectancy has begun to falter.
Plant power, as part of a balanced diet, can help us delay the onset and the severity of such chronic and degenerative conditions and diseases.
Research from the United States recently highlighted that women who eat in line with dietary recommendations have a 30 percent lower risk of dying from any cause than women who don't.
And the World Cancer Research Fund advises we eat a diet rich in a variety of fruit and vegetables which could prevent at least 20 percent of all cancers.
Fortunately, nutritional research, public nutrition education, and people's increasing knowledge about how to eat well is steering us in the right direction.
Traditional Dietary Patterns
Plants have been viewed as healing foods for thousands of years. Garlic was a favorite of the Greeks, Romans, and Egyptions; ginger was used extensively throughout Asia; and olive oil was revered by the Minion civilizations of Crete.
The health benefits of three classic cuisines - the Mediterranean diet, the Japanese diet, and the vegetarian diet - are supported by a large body of population and clinical studies.
With the global variety of foods now available to us, it has never been easier to maximize these benefits.
THE MEDITERRANEAN DIET
The Mediterranean diet hails from the dietary traditions of populations bordering the Mediterranean sea.
Olive oil is the main source of fat, and wine is the favorite beverage.
It is a vibrantly colorful cuisine and full of satisfying flavor, with only small amounts of poultry, meat, and dairy products.
This diet is associated with a lower risk of coronary heart disease, high blood pressure, diabetes, and certain cancers.
A study showed that when adopted by Westerners recovering from a heart attack, a Mediterranean-style diet was more heart protective than a low fat diet.
The traditional Mediterranean diet is low in cholesterol-raising saturated fat and rich in powerful plant foods.
The recommendation by the World Health Organization to eat at least five portions of fruit and vegetables each day was based on the Mediterranean diet, and its association with a low risk of chronic
diseases.
THE JAPANESE DIET
Compared to the West, the long-lived Japanese enjoy lower rates of coronary heart disease, obesity, breast and prostate cancer, osteoporosis-induced hip fracture, and menopausal symptoms.
Japanese people living in Western countries have similar health problems to their local compatriots, suggesting that diet and lifestyle play a major role in the Japanese health advantage. Sadly, incoming Western food habits are now influencing health in Japan.
The traditional Japanese diet centers on rice, soy beans, fish, seafood, and vegetables. Noodles, seaweed, spices, and fruit are also enjoyed.
Meat is used more as a garnish or to flavor sauces.
Presentation is paramount. Its only drawback is its high salt content.
Fish and soy beans provide a good supply of essential omega 3 fats. And the humble soy bean (the focus of recent nutritional research) no doubt contributes to the benefits of the Japanese and other Asian diets.
THE VEGETARIAN DIET
About five percent of Western populations now claim to be vegetarian.
Studies on the diet and health of vegetarians in Britain and the U.S. confirm that vegetarian diets tend to be lower in saturated fat (not necessarily total fat), and richer in fiber and phytonutrients than the diets of omnivores.
Vegetarians also tend to be slimmer, suffer less from high blood pressure, diabetes, and gallstones. They also have lower rates of heart disease.
You don't need to be strictly vegetarian to enjoy similar health benefits. The fact that a variety of plant foods forms the bulk of this diet (rather than simply not eating meat), seems to be the key.
KEY FUNCTIONS OF PHYTOCHEMICALS
Our parents were quite right when they told us to eat our greens. Research into phytonutrients in fruit, vegetables, and other plant foods is already revealing a range of mechanisms to explain how they might
work to protect our health.
It is clear than plant foods are good for our health - and the phytonutrients they contain are partly responsible.
What is less clear is exactly why this is.
In laboratory studies, and some human studies, different phytonutrients have been shown to have the following types of effects.
- Antibacterial, antiviral, antifungal
- Immune system stimulating
ANTIOXIDANTS EXPLAINED
A number of these phytochemical effects may be to to their influence on enzymes, others are linked to their ability to work as antioxidants.
An antioxidant protects against the effects of oxidation.
Think of it in terms of a rusty iron nail. Oxygen in the air reacts with iron to form rust.
Oxygen can also react with fat, say in butter, and turn it rancid.
As we all breathe in oxygen, similar oxygen-related processes happen in our body.
And without the protective effects of antioxidants, these unchecked oxygen reactions could "rust" our bodies over time.
FREE RADICALS
Every cell in the body uses oxygen to produce energy and allow the body to function.
This is a normal part of the body's metabolism.
While all these oxygen reactions are happening, very unstable molecules know as "free radicals" can be produced.
Free radicals are unstable because they are missing an electron.
However, they are very quick to snatch an electron from somewhere else in the body - for example, from a body cell - to help them become stable again.
This action can damage body cells and also trigger the formation of another free radical, and so a chain reaction starts.
Antioxidants can save the day by giving up one of their own electrons and neutralizing free radicals.
This stops cell damage and eventually the chain reaction
Free radicals are also deliberately made by the cells of our immune system to destroy invading bacteria and viruses.
Free radicals are also increased in the body by pollution, UV sunlight, radiations, cigarette smoke, stress, and excess polyunsaturated fat.
Overall, we are exposed to around ten million free radical "hits" every day.
The body produces some antioxidants, but damage can develop if free radical production becomes excessive.
This is called "oxidative stress."
Damage caused by oxidative stress accumulates with age, and some scientists believe the early aging and chronic health problems (e.g., cancer, heart disease, cataracts, rheumatoid arthritis, Alzheimer's disease) are initiated by free radical damage, then take years to develop.
The body's ability to produce its own antioxidants may also decline with age.
Finally, different antioxidants may neutralize free radicals in different parts of the body and regenerate one another.
This means that getting a range of different antioxidants from a variety of foods throughout our lifetime is very important.
The antioxidant defense system limits free radicals from;
- Damaging cholesterol-carrying particles, known as low-density lipoprotein or "bad" LDL cholesterol, which may increase the risk of atherosclerosis.
- Contributing to the formation of blood clots (thrombosis), which may increase the risk of a heart attack or stroke) over time
- Damagine a cell's genetic material (DNA), which may lead to cancer.
- Suppressing the immune system.
Defending against all these effects may slow the progression of chronic disease and aging.
CANCER-FIGHTING PHYTOCHEMICALS
One in three people will develop cancer at some time in their lives.
Cancers can start when the DNA or genetic material in cells in damaged (known as "initiatian") by carcinogens.
Years may pass before the cancer becomes noticeable.
Cancerous cells grow in an unrestrained way, invade and damage healthy tissues, and can spread to other parts of the body - forming secondary growths (metastases).
Some phytonutrients seem to stimulate enzymes that block carcinogens or suppress this spread of cancer cells.
Others with anti-oxidant effects may help the immune system to remain strong and destroy any damaged cells.
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