Dark berries like blueberries and cranberries are increasingly recognized in the public as health icons. Not only nutritious by their contents of vitamins, minerals, amino acids, protein and dietary fiber, berries are also synonymous with antioxidant health benefits.
Antioxidants are an important nutrient category thought to be the major health characteristic of colorful fruits and vegetables. Antioxidants are substances synthesized in our bodies or obtained via edible plant chemicals that can prevent or slow oxidative stress to our body’s cells. More than 60 diseases, including cancer, diabetes, inflammatory, neurological and cardiovascular diseases, are linked to oxidative stress that may be relieved by dietary antioxidants.
Scientists believe that plants make antioxidant chemicals to protect the plant’s regenerative capacity from the damaging effects of constant exposure to sunlight, ultraviolet radiation, infections, pests, injury and oxygen radicals produced during photosynthesis. These antioxidants are found in their highest concentrations in the fruit skin (or rind) and seeds.
Antioxidant phytochemicals, such as the blueberry anthocyanins, contribute scent and blue pigment to the berry skin. This plays a useful regenerative role to attract insect pollinators and birds that eat the fruit and then disperse the seeds in their droppings.
Plants also benefit from antioxidant protection in their skin against ultraviolet radiation, photo-oxidative processes, and viral or bacterial pathogens. These are benefits that can be passed on to animals and humans who consume the berries.
Oxidative Stress and “Pigment Power”
Without protective antioxidants from pigments like anthocyanins in berry skin, reactive oxygen species (ROS) are created during normal photosynthesis leading to oxidative injury. These injuries affect proteins, lipids and nucleic acids, and can cause alteration in gene transcription and even lead to programmed cell death (a process scientists call “apoptosis”, eh-poh-toe-sis) in the fruit or its seeds. Some botanists and food chemists refer to this protective benefit as “pigment power”, which is desirable to obtain through the human diet. We acquire this transfer of protection by eating fruits, vegetables and animal sources that have color-rich pigments. Dark berries are an excellent source of these pigments.
Within colorful berries we can find many members of the pigment group called “phenolics.” Each member provides antioxidants, color, scent, and flavor qualities. The following is just a sampling of the thousands of edible plant phenolics. Any one berry species may contain dozens of antioxidant pigments. Each of the berries below is a rich source of anthocyanin pigments; a few of which are listed where medical and food science have revealed preliminary evidence for health benefits.
Here is a list of the antioxidants found in the following berries:
o Blackberries: gallic acid
o Black raspberries: ferulic acid
o Blueberries: anthocyanins, chlorogenic acid, peonidins
o Cranberries: proanthocyanidins, catechins, quercetin
o Elderberries: myricetin
o Red raspberries : ellagitannins, procyanidins
o Red grapes: resveratrol, proanthocyanidins (seeds), catechins
o Strawberries: ellagic acid
ROS – Radical Oxygen Species
When human cells use oxygen, they naturally produce ROS as by-products of normal metabolism. This can lead to cell damage if normal counter-balances are absent in the environment inside and around cells. ROS are also called “oxygen free radicals” or elements so reactive they are “free” to interact with numerous cells and chemicals in the body, often in a way that is damaging.
Antioxidants synthesized internally or introduced from our diets act as neutralizing sponges or “scavengers” of ROS. By donating electrons sought by the free radical, antioxidant molecules serve to counterbalance, absorb, quench, prevent or repair damage done by ROS.
However, when balancing mechanisms are ineffective, perhaps because of a diet poor in antioxidant foods or during the decline of body functions with disease or aging, ROS disperse randomly in a concentration gradient from their point of formation. There, if unchecked by antioxidants, they can cause damage within cells and to nearby cells, that can contribute to disease and aging. This is one of the leading theories for how Alzheimer’s disease progressively destroys neurons.
Oxidative Stress and Dietary “Therapy”
Most diseases are initiated and perpetuated to some degree by ROS and by insufficient amounts of internal and dietary antioxidants. These are the underlying conditions for “oxidative stress” which may explain a sizable component of aging.
If chronic, oxidative stress can lead to an increased risk of developing the following diseases:
• Cancer
• Cardiovascular and inflammatory disorders
• Diabetes
• Neuronal degeneration (e.g., Alzheimer’s and Parkinson’s disease)
• Macular degeneration causing vision loss and general deterioration of aging
• Chronic sickness
Measuring Antioxidant Strength: ORAC
The term ORAC, standing for “oxygen radical absorbance capacity”, is a numerical way of representing antioxidant strength in berries and other foods. When antioxidants are present in a food, their collective strength can be measured in the test tube assay called ORAC.
Recently, scientists working with the US Department of Agriculture published a database of ORAC values.
Dark berries, especially wild and cultivated blueberries, blackberries and cranberries, stood out with the highest ORAC values among some 25 fruits tested. Their values were in a range of about 7,000-13,000 ORAC units per Cup or 250 ml serving.
Preliminary North American guidelines recommend at least 5,000 ORAC units per day for the adult diet. Doubling that number would not only be safe for antioxidant reserves, but would also provide antioxidant qualities that would supply numerous essential macro- and micronutrients. Most importantly though, it would make for enjoyable eating!
The ORAC test will likely gain public acceptance as a standard measure allowing comparisons of freshness and antioxidant strength in different foods. This standard will facilitate selection of high ORAC foods and relate antioxidant capacity to potential protection of health. For example, there is already scientific evidence for an inverse correlation between dietary intake of antioxidant foods and incidence of some cancers (US National Cancer Institute).
Antioxidant Berries
Wild Blueberry (Vaccinium angustifolium).
Wild lowbush blueberries have nearly 50% greater antioxidant strength than their cultivated cousins – the highbush blueberry – that is so popular in grocery stores. Wild blueberries score highest in ORAC among common (but not all) berries, having about 13,000 ORAC units per Cup or 250 ml. Over the past 10 years, the focus of food scientists on health properties of wild blueberries has revealed a compelling story of nutrient richness and diversity of potential health benefits, including:
• Urinary tract health (identical in strength to cranberries)
• Inhibition of cancer development
• Cardiovascular protection
• Mental alertness
• Vision support
Blackberry (Rubus ursinus)
The juicy delicious dark blackberry has great taste and nutrient richness. Confirming the idea that the darkest berries correlate with the strongest antioxidant activity, science has recently demonstrated that blackberries have some of the densest concentrations and widest diversity of phenolics found in the plant world. Blackberry’s ORAC is nearly 8000 units per Cup or 250 ml.
Black raspberry (Rubus occidentalis)
“Blackcaps” are a little-known powerhouse of antioxidant richness and outstanding taste. Isolates from black raspberries were shown in laboratory tests to specifically starve tumor cells by preventing growth of new tumor blood vessels. Overall a more powerful antioxidant berry than even the wild blueberry (ORAC > 15,000 per Cup or 250 ml), blackcaps contain a toolkit of flavors and nutrients.
Cranberry (Vaccinium macrocarpon)
The North American cranberry has become famous for its popular juice. Known well for its anti-adhesion properties, which inhibit bacterial infections in the urinary tract, cranberry extracts have shown anti-cancer and cardio-protective effects in laboratory studies. These results occur mainly from the cranberry’s abundant supply of antioxidant phenolics that also make it a promising agent for blood, brain and vision health.
Elderberry (Sambucus nigra)
Another phenolic-rich dark berry with a delectable taste, the elderberry has been associated with many of the potential health benefits already mentioned. It has stood out particularly in laboratory tests for its anti-inflammatory and urinary tract benefits. The elderberry also shows promise for anti-bacterial and anti-viral effects that may offer protection against such virulent pathogens as Salmonella, E. coli, H. pylori and Staphylococcus.
Red Raspberry (Rubus idaeus)
The red raspberry is well loved for its subtle distinct flavor but is also a wonderful store of antioxidant phytochemicals, particularly one called ellagic acid. One of its other constituents, a ketone, was shown in recent laboratory studies to stimulate fat metabolism, causing experimental animals to lose significant weight.
Red Grape (Vitus vinifera)
The red grape is valued for its familiar popular taste and diverse number of phenolics residing mainly in its skin and seeds. Especially rich in the phenolic called resveratrol, a powerful antioxidant, red grapes are linked to having a possible beneficial effect on:
• Alzheimer’s disease
• Heart disease
• Cancer
• Osteoarthritis
• Other aging disorders
Strawberry (Fragaria vesca)
Containing a host of antioxidant phenolics, the strawberry’s constituents may be particularly important as natural blood-thinners, anti-fungal agents and inhibitors of oxidizing effects on cells from chronic stress.
Other Antioxidants
Other phenolic antioxidants mentioned in current public media include:
• Apigenin
• P-coumarin
• Kaempferol
• Caffeic acid
• Hydroxycinnamic acid
• Tannic acid
• Salicylic acid (similar to aspirin)
These pigment chemicals belong to the flavonoid subclass of the phenolic super-family and are present among dark berries.
Color-rich plant foods like berries offer a delicious, nutritious way of keeping dietary intake of antioxidants high. Eat color! Gain ORAC! Live Well!
Reading
* PubMed, US National Library of Medicine, http://pubmed.gov
* Wild Blueberry Association of North America, http://www.wbana.org
* Wu X et al., Lipophilic and hydrophilic antioxidant capacities of common foods in the United States. J Agric Food Chem 52:4026-37, 2004.
Copyright 2006 Berry Health Inc. Dr. Paul Gross is a scientist and expert on cardiovascular and brain physiology. A published researcher, Gross recently completed a book on the Chinese wolfberry and has begun another on antioxidant berries. Gross is founder of Berry Health Inc, a developer of nutritional, berry-based supplements. For more information, visit http://www.berrywiSEOnline.comWordPress Autoblogging Plugin

Meet the “New-trients”
Today’s consumers are witnessing a new era in how foods are identified. New nutrients, not commonly understood for their health benefits, seem to be popping up on our grocer’s shelves every day. Omega fatty acids, newly defined sources of dietary fiber, and antioxidant phytochemicals are examples of healthful plant elements that are creeping into public media reports and water-cooler debates.
Laboratory and preliminary human clinical studies are revealing anti-disease properties of these “nutrients.” Extensive food and medical research underway presently will eventually translate the chemical properties into consumer understanding and terminology that we’ll grasp and use in everyday conversation.
With such potential significance to public health, the consumer education process should begin now in a way that people, from teenagers to grandparents, can readily understand antioxidants as easily as we now understand calories, carbohydrates, fat percentage, and vitamin C.
The scientific and regulatory bodies for food labeling have a great challenge ahead of them.
There are thousands of plant food sources with suspected health benefits with complicated chemical names that are unfamiliar and can be intimidating. The challenge at hand is to decipher this blizzard of names and to promote better nutrition for our families and for ourselves.
Why Antioxidants?
The beneficial antioxidant chemicals that we get from colorful plant foods represent our best defense against threatening oxidants. While oxidative stress is a normal part of cellular metabolism that occurs even in healthy people, left unchecked, it can lead to damage that accumulates with age.
Normally, oxidative species or “free radicals” are neutralized by antioxidant enzymes and food-derived antioxidants. However, the following circumstances can cause an imbalanced oxidant-antioxidant relationship that allows oxidative stress to go unopposed.
• Contamination by environmental conditions like pollution, radiation, cigarette smoke and herbicides
• Normal aging
• Poor diets that lack essential nutrients and phytochemicals
The result of this imbalance is cell and tissue damage that could lead to diseases like:
• Cancer
• Hypertension
• Diabetes
• Chronic inflammation
• Neuronal degeneration like Alzheimer’s disease
The Color Code for Antioxidants
Over the past five years, we have begun a valuable process for recognizing plant food antioxidant qualities by groupings of color—The Color Code, as written in two books entitled The Color Code and What Color is Your Diet? (publication information below).
The following is a summary of those color guides for antioxidants, and an example of how we can begin to classify and categorize the different antioxidants into the food color code.
Summary of the Color Code
This is a general scheme of example foods that can fit into each color class. Keep in mind that there are no firm lines between the classes, which allows for overlap.
1. Red – tomato, pink grapefruit, watermelon
2. Blue/Red/Purple/Black (BRPB) – blueberry, cherry, prune, blackberry
3. Orange/Yellow – carrot, pumpkin, orange, papaya
4. Green – broccoli, kale, spinach, pea
5. White – garlic, onion, cabbage, turnip
6. Brown/Gray – spices, nuts, seeds, endogenous sources
How to Apply the Color Code
Here’s a general breakdown of the color groups that have food chemicals with antioxidant qualities:
1.Enzymes (Brown/Gray)
A protein substance with a name ending in “ase”, enzymes stimulate biochemical reactions in living cells and help form new compounds that, in this case, would serve antioxidant functions.
Members of this enzyme class of antioxidants include:
• Superoxide dismutase
• Catalases
• Reductases
• Peroxidases
• Transferases
2.Vitamins (Brown/Gray)
Most consumers would already recognize the three main antioxidant vitamins—A, C and E—that are derived from food and supplements common to the public. Vitamins A and E are fat-soluble, providing antioxidant protection in cell structures like the outer membrane and inner nuclear organelles. Vitamin C dissolves readily in body water compartments, so it is well distributed in the body. Of particular note is the important role of vitamin C in protecting vitamins A and E from damaging oxidative free radicals.
3.Phenolics (BRPB)
With more than 8,000 individual chemicals that serve plants as pigments, the phenolics (also called phenols or polyphenols) are water-soluble acids that not only give plants colors, but also differentiate scents, tastes, and bitterness. The large class of phenolics (called flavonoids) is often mentioned in current public media. Quercetin, kaempferol and peonidin are examples of flavonoids that have been in the news recently.
4.Carotenoids (Orange/Yellow, Red)
A fat-soluble group of more than 600 individual chemicals, the carotenoids (e.g., beta-carotene, lycopene, lutein and zeaxanthin “zee-a-zan-thin”) are especially powerful antioxidants. Due to their chemical structure, they are an excellent source of electrons that are aggressively sought by oxidative free radicals. A carotenoid molecule donates electrons to a free radical, sacrificing itself in antioxidant defense. Terpenes and xanthophylls are included in this class.
5.Hormones (Brown/Gray)
A growing field of medical research is identifying normal hormones typically described with cell-to-cell messaging roles in the body as having antioxidant functions. Presently only a few hormones have this identified property such as melatonin, estradiol and insulin, but future research will likely unravel similar functions for the dozens of hormones known in human physiology.
6.Minerals (All colors)
Minerals have elements that enable enzyme activity. Selenium, zinc, manganese, magnesium and copper are minerals involved in hundreds of antioxidant roles in the body.
7.Glutathione (Brown/Gray)
Probably the human body’s single most important native antioxidant, glutathione is a water-soluble molecule synthesized from food-derived amino acids. It also depends on lipoic acid (below) for synthesis.
8.Lipid effectors (Orange/Yellow)
Lipoic acid is perhaps the “perfect” antioxidant because it is a small powerful molecule that dissolves readily both in fatty layers of cells and in water – the only antioxidant to do this. Other lipid oriented antioxidants include omega fatty acids, tocopherols (like vitamin E), phytosterols, perillyl alcohol and essential oils such as limonene.
9.Saponins, steroids and stilbenes (Green, BRPB)
Related in this discussion only by their common first letter “s”, this group has established antioxidant functions and includes some well-known chemicals such as resveratrol (a stilbene of red wine and dark grapes), brassinosteroid (the growth regulator of plants) and saponin (the waxy covering on plant leaves).
10.Sulfur-containing chemicals (Green, White)
Including organosulfides, tri and diallyl sulfides and sulforaphane, this group from plants like broccoli and cabbage has been shown to have properties affecting antioxidant enzyme activity, inflammatory mediators and tumor growth.
Proposing an Antioxidant Nomenclature
Just as vitamins have been given a nominal identity (Vitamin A, B, C…etc) so too should we refer to antioxidants. This is a new system not yet formally proposed to any regulatory authority or scientific body. Classification of antioxidants must undergo the scrutiny, revision and adoption by scientists, industry and government to be acceptable for food label use in the public.
Here is the proposed breakdown:
1. Antioxidant C – carotenoids
2. Antioxidant E – enzymes
3. Antioxidant G – glutathione
4. Antioxidant H – hormones
5. Antioxidant L – lipid-associated chemicals
6. Antioxidant M – minerals
7. Antioxidant P – phenolics
8. Antioxidant S – saponins, steroids, stilbenes, sulfurs
9. Antioxidant V – vitamins
Over time, the public must feel these proposed antioxidant classes are informative and practical for understanding antioxidants and choosing preferred foods. Time will tell, but this list gives us a simple working structure to get a handle on naming antioxidants.
Reading
* Heber D. What Color Is Your Diet? HarperCollins, New York, 2001.
* Joseph JA, Nadeau DA, Underwood A. The Color Code, Hyperion, New York, 2002.
* Lee J, Koo N, Min DB. Reactive oxygen species, aging, and antioxidative nutraceuticals. Compreh. Rev. Food Sci. Food Safety 3:21-33, 2004.
Copyright 2006 Berry Health Inc. Dr. Paul Gross is a scientist and expert on cardiovascular and brain physiology. A published researcher, Gross recently completed a book on the Chinese wolfberry and has begun another on antioxidant berries. Gross is founder of Berry Health Inc, a developer of nutritional, berry-based supplements. For more information, visit http://www.berrywiSEOnline.comtruth about diets