Goji Berry Vitamina C

Goji berries -- pronounced "go-gee" -- are a recent hot commodity in the increasingly trendy high-end health food industry. These delicate red berries, traditionally grown in the Himalayan valleys of China, Mongolia and Tibet, as well as in the Xingjiang and Ningxia provinces of China, have been featured on Oprah, and celebrities like Madonna, Mischa Barton and Elizabeth Hurley are swearing by them. Numerous goji berry products have appeared on the market, promising youth, good health, cancer-fighting abilities and an increased sex drive. A Google search for "goji berry" yields 378,000 results, many of them for various products containing goji berries or goji berry "extract" (juice). So are goji berries a miracle "superfood," just another product of the hype machine or something in between? Let's find out.

Goji berries, also called wolfberries, have been grown in the Himalayan valley for hundreds of years. Traditional Chinese folk medicine uses them to cure a variety of ailments. Goji berries have also long been used in various Asian dishes as an ingredient or a garnish. Goji berry bushes grow to be one to three meters high . Because the berries are very delicate when on the plant, they cannot be picked by hand. Instead they are gently shaken from the vine. Frequently they are set out in the sun to dry, whereupon they become slightly chewy. Besides eating the berries, you can also drink the goji berry juice. It is especially popular in the regions where the berries are grown, and can be combined with tea to make a tonic.

Image credit: photo used in public domain
Because of their delicacy, goji berries must be shaken off of the plant when harvested.
See more fruit pictures.

Special Thanks

Thank you to David Boyd, Director of Global Operations for Pure Fruit Technologies, for providing images used in this article.

Numerous goji berry products are being marketed in the West. Among the most popular are dried goji berries and goji berry juices, which are frequently made up of goji berry juice mixed with water or other fruit juices. Health food and specialty stores also sell teas, pure goji berry juice, goji berry extract in capsule form, goji berry crunch bars and granola cereals with goji berries. In the fall of 2006, goji berries became a huge hit in the United Kingdom, and Tesco, the UK's largest retailer, began selling them.

Some goji berry lovers appreciate the taste, comparing it to a cranberry or a cross between a strawberry and raspberry. Many of them buy the berry because of its reputed health benefits. In the next section, we'll take a look at the nutritional and health benefits of goji berries.

Benefits of Goji Berries

Goji berry marketers have made bold claims about their products' powers: Goji berries can prevent or even cure cancer. They provide more oxidants than any other fruit. They boost sexual function and keep people looking and feeling young. Of course, not all of these claims are true, and some may be difficult to verify. But there are some things about goji berries that we can determine with certainty.

Goji berries are incredibly nutritious. For their weight -- a daily serving is only 10 to 30 grams -- goji berries have more vitamin C than oranges, more beta carotene than carrots and more iron than steak. Beta carotene is believed to help fight heart disease and also protects the skin from sun damage. Goji berries are also a good source of B vitamins and antioxidants, which protect against harmful free radicals that damage cells in your body. They're also rich in polysaccharides, which aid the immune system, have 18 kinds of amino acids, and are a rich source of potassium. And, as if protecting your heart, skin and immune system weren't enough, beta carotene and antioxidants are thought to help fight cancer.

In fact, the claim that goji berry producers frequently refer to is the fruit's supposed cancer-fighting power. This ability, they say, stems from goji berries' high antioxidant content. Antioxidants are actually a class of vitamins that includes beta carotene and vitamins E and C. Goji berries rate highly in terms of Oxygen Radical Absorbance Capacity (ORAC), a test developed by the U.S. Department of Agriculture. Here are ORAC values (in units per 100 grams) for some foods with high amounts of antioxidants:

Prunes – 5,770
Raisins – 2,830
Blueberries – 2,400
Kale – 1,770
Strawberries – 1,540
Spinach – 1,260
Brussels sprouts – 980
Plums – 949
Oranges – 750

According to several sources, goji berries' ORAC value is more than 25,000! But what does this mean?

Image credit: photo used in public domain

Dried goji berries have become a popular, healthy snack, especially in the UK.

In 1999, the U.S. Department of Agriculture released the details of a study finding that foods with high ORAC values may help to slow the aging process and to protect cells from oxidative damage (from free radicals). The 25,000 ORAC number is difficult to verify, but if it is to be believed, it doesn't mean that we should abandon all other antioxidant-carrying fruits for goji berries. Antioxidants are good for the body, but like many vitamins and minerals, there's only so much we can absorb. Anything more than a certain amount will pass through the body unprocessed. In the case of selenium, which is found in goji berries, the right quantity helps to keep your liver healthy; too much can be toxic. For that reason, it's good to stick to somewhere around the daily serving of goji berries –- 10 to 30 grams -- and to mix other healthy, nutritious foods into your diet.

Do we need supplements?

The Cleveland Clinic, in a survey of numerous studies on antioxidants and supplements, found that excessive amounts of Vitamin E and beta carotene supplements increased the risk of heart disease. They still recommended eating foods rich in vitamins and antioxidants. The Mayo Clinic also recommends avoiding high antioxidant supplements until their effects are better known. Some antioxidant supplements contain thousands of times the amount found in food sources, so in general, it's safer to stick to foods that you know are safe and nutritious.

Scientific Experiments

Because of its long history in Chinese culture, medicine and food, many studies involving goji berries have been performed at Chinese universities. A search on PubMed, a repository of millions of medical and scientific papers, produces 50 articles on Lycium barbarum, the scientific name for goji berries. Only one of these studies tested goji berries' effects on cancer. The information available about the experiment is vague; an English-language abstract is available, but the full article is in Chinese. The study reports a significant improvement in patients who took cancer drugs and a goji berry extract versus patients who just took cancer drugs. However, the cancer therapy used was a once popular therapy that is now rarely administered [ref]. There are also numerous unanswered questions about the standards employed in the study. Among them are the following:

What is considered significant improvement?
How many people are involved in the study, and can it be replicated?
Were there any side effects?
Did the results diminish over time, and were any follow-up studies conducted?

Unfortunately, this study is far from definitive. The antioxidant capacity of goji berries is indisputable, and antioxidants are widely believed to help prevent cancer. More tests will have to be conducted, though, before goji berries can be considered part of a viable cancer treatment.

Let's look at some more studies involving Lycium barbarum.

Goji Berries and Diabetes

A 2004 study at the College of Public Health at Wuhan University tested the effects of goji berry extract on diabetic rabbits. The scientists found an increase in HDL, or "good," cholesterol in the rabbits and a reduction in blood glucose level.

Anti-aging Effects

In 2006, scientists at the School of Food Science and Technology of the XingJiang Agriculture University tested the anti-oxidant effects of Lycium barbarum versus vitamin C on older mice. The polysaccharides from the Lycium barbarum helped to compensate for "the decline in [total antioxidant capacity], immune function and antioxidant enzymes" [ref]. The polysaccharides were also found to fight free radicals.

These studies, while encouraging, cannot be considered definitive until they are attempted on humans and the results are published and reviewed by the scientific community.

Toxicity

Past investigations of Barbary wolfberries from India had expressed concern about levels of atropine, a toxic substance, in the berries. In September 2006, scientists at the University of Graz in Austria took eight samples from wolfberries grown in China and Thailand. Once analyzed, the samples showed levels of atropine, but they were far below toxic levels.

How Goji Berries Keep You Young

The Ningxia Hui region of Northern China, where goji berries are grown and eaten on a daily basis, has 16 times as many centenarians -- people 100 years old or older -- as the rest of the country. As residents of the region age, they are much more active, healthy and vibrant than their peers in Western cultures. The small, red goji berry, traditionally regarded as the "longevity fruit," is a key ingredient in their healthy diet. Researchers who study medicinal plants have identified a variety of nutrients in the goji berry that may help people enjoy longer and healthier lives. Let's look at the anti-aging properties of these small berries.

Protecting DNA with Antioxidants

Damage to our DNA opens the door to every imaginable disease and accelerates aging. In the course of living, our DNA is damaged by free radicals generated as a byproduct of normal metabolism and by exposure to toxins.

Although our bodies are equipped to continually repair themselves, they can become overwhelmed by too many free radicals, especially as we age. This results in the premature death of healthy cells, which may contribute to a variety of degenerative diseases and mutated cells that can lead to cancer -- unless antioxidants counter the onslaught.

Vitamins, minerals and amino acids may have antioxidant properties. Here are some of the key antioxidant nutrients found in goji berries and vital body functions they support, in addition to fighting free radicals:

Antioxidants in Goji Berries	Body Functions Supported
Vitamin C	Heart health
Beta-carotene	Immunity
Cystine	Immunity, healthy stomach lining
B2 (riboflavin)	Conversion of carbohydrates into fuel
Manganese	Healthy skin, bone, cartilage
Zinc	Wound healing, fertility, vision, immunity
Copper	Energy, hormonal function, healthy skin
Selenium	Healthy liver, thyroid, immunity, cancer protection

Sources: Wolfberry: Nature's Bounty of Nutrition & Health and www.supplementinfo.org.

Promoting Human Growth Hormone Production

Levels of human growth hormone decline as we age. A 70-year-old produces only one-tenth of the amount generated by a 20-year-old. This decline parallels physical deterioration, such as lower levels of energy, muscle wasting and a tendency to store more body fat. Boosting the natural production of growth hormone helps us feel, look and function like a more youthful person. Goji berries help our bodies do this in two ways:

Potassium: Goji is a rich source of the mineral, which is vital for health and longevity. Insufficient potassium interferes with the normal function of the pituitary gland, which produces growth hormone.
Amino acids: Certain amino acids promote the production of growth hormone. Goji is a rich source of l-glutamine and l-arginine, two amino acids which may work together to boost growth hormone levels and revitalize youthful appearance and function.

Enhancing Libido and Sexual Function

Diminished sexual function is not an inevitable part of aging. A lower sex drive in both men and women can be associated with decreased production of testosterone. Goji berries can help by increasing its production.

In Asia, goji berries are traditionally regarded as a strong sexual tonic. In addition, goji acts as a general tonic to improve overall stamina, mood and well-being. It can also help to decrease stress. All of these benefits are conducive to a healthy sex life.

Increasing Energy

The goji berry is an "adaptogen," a term used in the world of medicinal plants to describe a substance with a combination of therapeutic actions. An adaptogen invigorates and strengthens the system while helping the body to deal with stress without collapsing. It also supports healthy function of the adrenal glands, which tend to get overworked in times of stress.

Goji berries are considered to be an especially beneficial adaptogen in Asia. The goji is believed to harmonize functions of the entire body, resulting in enhanced stamina, strength and energy.

Improving Vision

The goji berry contains two key nutrients for healthy vision: zeaxanthin and lutein. These are concentrated at the center of the retina and protect the eye from the most common causes of age-related loss of sight, including macular degeneration, cataracts and diabetic retinopathy.

Free radicals also attack the eyes, and zeaxanthin and lutein protect against such damage. Animal research in China has shown that eating goji berries can reduce free radical damage of the retina.

Controlling Cholesterol and Blood Pressure

Super Potassium

A 3-ounce serving of dried goji berries contains 1,600 mg of potassium -- four times the potassium in three ounces of banana.

Goji berries have the ability to combat two key factors that promote heart disease: oxidized cholesterol and elevated blood pressure.

Cholesterol becomes especially dangerous when it oxidizes as a result of free radicals, and the oxidized blood fats then attach to artery walls as plaques. Our bodies have a built-in defense system, an enzyme called superoxide dismutase (SOD). SOD produces antioxidants to prevent cholesterol from oxidizing, but levels of SOD decline as we age.

Chinese research shows that goji berries can increase our production of SOD, reducing oxidization of cholesterol. Goji berries also contain other antioxidants that decrease oxidation of cholesterol and help to control blood pressure.

Keeping Vital Organs Healthy

In addition to helping keep the heart healthy, goji berries help balance blood sugar and enhance the liver, digestive system and skin:

Blood sugar: Goji berries have been used in Asia for the treatment of diabetes and to help regulate high blood sugar, which is a precursor to both diabetes and heart disease.
Liver: Several types of phytonutrients in the fruit enhance the ability of the liver to detoxify and guard against the organ being damaged by carcinogens and the hepatitis virus.
Digestion: Goji berries are helpful for all types of digestive problems and can aid in recovery from digestive illnesses, such as ulcers and irritable bowel syndrome.
Skin: Goji berries contain fatty acids, which can stimulate collagen production and retain moisture, resulting in younger-looking skin.

Improving Sleep

Goji berries are a rich source of two nutrients that are necessary for healthful sleep:

Thiamin (B1): The vitamin is found in the hulls of grains, but it is missing from diets that mostly contain refined grains. Thiamin also improves mood, alleviates depression and increases energy levels.
Magnesium: The mineral reduces the time it takes to fall asleep and improves the quality of sleep.

Supporting Brain Health

How Goji Berries Strengthen Your Immune System

For more than 2,000 years, goji berries have been a staple remedy of traditional Chinese medicine. Known as the "longevity fruit," these small red berries also have unique immune-enhancing properties.

Your Immune System

Your body's immune system keeps you healthy by stopping foreign invaders, such as bacteria, viruses and carcinogens, from causing damage. It can malfunction in two ways. It can allow pathogens to attack, such as a cold virus. Or, it can mistakenly assume that some part of the body is an invader, attacking it and causing auto-immune disorders, such as:

allergies
cancer
multiple sclerosis
skin rashes or blisters
joint pain or stiffness
thyroid malfunction that results in tiredness, weight gain, sensitivity to cold or muscle aches
ulcerative colitis
rheumatoid arthritis
type 1 diabetes
lupus
celiac disease

Disease-Resisting Compounds in Goji Berries

Goji berries contain unique compounds known as Lycium barbarum polysaccharides, most often referred to as polysaccharides. Research has shown that these compounds enhance the body's ability to resist disease. Goji's polysaccharides have a chemical structure similar to substances found in echinacea and maitake mushrooms, herbs known for their ability to support a healthy immune system.

The berries are also a rich source of vitamin C and zinc, both of which are known to protect against disease and aid in recovery. Research at Case Western Reserve University has shown that zinc can shorten the length and severity of a cold. Zinc deficiencies are more likely to occur as we age and produce less stomach acid.

Vitamin C, an antioxidant, is needed for:

growth and repair of all human tissues
formation of collagen in skin, scar tissue, tendons, ligaments and blood vessels
wound healing
healthy cartilage, bones and teeth

Zinc, also an antioxidant, is needed for:

regulation of appetite, taste and smell
controlling stress
normal growth and function
healthy reproductive function in men and women

Auto-Immune Disorders

Immune cells are like guards that constantly police our bodies, looking for harmful intruders and attacking any they find. Problems arise when the immune cells misidentify healthy cells as invaders and attack these, essentially making the body turn on itself and triggering auto-immune disease. One in five Americans suffer from an auto-immune disease. Three out of four are women.

Goji berries help the immune system to distinguish more effectively between friend and foe. The fruit's polysaccharides provide cells with special sugars that support healthy immunity and enable cells to communicate more effectively with each other.

Author and pharmacist Earl Mindell calls goji's polysaccharides "master molecules" because they "command and control many of the body's most important biochemical defense systems."

Friendly Intestinal Bacteria

Goji berries also support healthy immunity by promoting the growth of beneficial bacteria in our gastrointestinal system. The fruit's combination of fiber content and polysaccharides naturally supports the growth of healthy intestinal bacteria, known as probiotics.

Probiotics have numerous benefits, including:

enhancing the function of the immune system
protecting against unhealthy bacteria that cause disease
aiding in the digestive process
reducing symptoms of digestive disorders such as irritable bowel syndrome
helping in recovery from respiratory infections
reducing the risk of allergies, including respiratory symptoms and allergic skin reactions

Healthy Proteins

The protein in goji berries, which makes up 16 percent of the fruit, contains two key amino acids that support the immune system: l-arginine and l-glutamine. Both of these are building blocks for healthy immunity and work to reduce inflammation.

Research Findings

For some time, scientists in China have been examining how goji berries work. In one study, after 50 people ate approximately 1.5 ounces of goji berries daily for 10 days, their white blood cell counts and other markers of healthy immune function improved.

Other studies have analyzed various actions of goji berries in test-tube and animal trials, and have found that the berries:

increased non-inflammatory immune cells that guard against bacteria and cancer
reduced inflammation and may be helpful in treating inflammatory diseases
inhibited symptoms of swelling and rheumatoid arthritis
enhanced immunity
may improve resistance to cancer cell growth

Allergies

Allergies occur as a result of some type of malfunction in the immune system, and can be triggered by many different substances in the environment, including food ingredients. In Asian medicine, they are traditionally treated with remedies designed to balance the immune system, rather than suppressing symptoms with medications.

In Asia, goji berries have traditionally been used as a therapy for allergies. Chinese scientists have observed that the fruit reduces antibodies that are generated in response to an allergen. In addition, the polysaccharides in goji are believed to enhance normal function of the immune system. The net effect is a restoration of healthy immune function.

Cancer

A healthy immune system is able to defend against the spread of mutated, cancerous cells. The immune system's natural killer cells are designed to target abnormal cells that develop into cancers. However, if the immune system is not able to do its job or attacks the body, the defense system breaks down and sets the stage for cancer growth.

Goji berries contain germanium, a mineral that is believed to have anti-cancer properties. In addition, its polysaccharides and antioxidants are believed to protect against free radicals that promote cancer and help to prevent cancer from developing.

Chinese studies show that goji berries inhibit some of the gene mutations that lead to cancer and that the fruit has anti-tumor properties. In addition, the berries may also help with the side effects of chemotherapy or radiation treatment for cancer.

How Goji Berries Help You Lose Weight

If you're like millions of other people who have difficulty losing weight, you probably engage in two common behaviors: You can't control your appetite -- especially your cravings for sugary, starchy foods -- and you don't have enough energy to exercise regularly. Nutrient-rich goji berries directly target these two weight-losing obstacles.

The Vicious Cycle of Cravings

High-calorie sugary and starchy foods tend to have little nutritional value. Instead, they trigger a hormonal reaction that leads to uncontrollable cravings. The process works like this:

You eat a sugary, starchy food and your body quickly converts it to blood sugar.
Your levels of blood sugar spike upward.
In response, your pancreas produces a high level of insulin.
Your blood sugar levels crash.
The roller-coaster effect causes cravings for more sugary, starchy foods.
The cycle repeats.

The speed at which a food converts to blood sugar (glucose) is measured on a numerical scale known as the glycemic index (GI). The lower the GI of a food, the more slowly it converts to blood sugar and the less likely it is to stimulate uncontrollable urges to eat empty calories.

The Low Glycemic Index of Goji Berries

On the glycemic index, a value of 100 is assigned to pure glucose. Foods rated at 70 or higher are considered high-GI, while foods rated below 55 are considered low GI and are more likely to satisfy rather than increase the appetite. Here's how the GI of goji berries compare with some other fruits:

Goji berry - 29
Apple - 38
Orange - 42
Banana - 25
Cantaloupe - 65
Raisins - 64
Watermelon - 72

More Ways of Controlling Appetite

Goji berries have additional characteristics that help control blood sugar and appetite. They contain 21 percent fiber by weight. High fiber foods are filling and moderate blood sugar levels. The berries are also a good source of chromium, a mineral that aids in blood sugar control. Chromium may also help to preserve lean muscle mass during weight loss. Muscle burns more calories than fat, promoting a more efficient metabolism, which makes it easier to prevent weight gain.

Burning Food for Energy

Goji berries are rich in several nutrients that help to convert food into energy rather than storing it as fat:

B1 (thiamin): The vitamin is essential for converting carbohydrates into energy and for healthy thyroid function. A sluggish thyroid gland promotes weight gain.
Calcium: In addition to supporting healthy bones, adequate calcium has been linked to lower levels of body fat.
Other minerals: A balanced combination of essential minerals is necessary for efficient protein metabolism. In addition to calcium and chromium, goji berries contain copper, iron, magnesium, manganese, phosphorus, potassium, selenium, sodium and zinc.

Promoting Lean Muscle

A lean body burns food as fuel rather than storing calories as fat. When we are young, abundant levels of human growth hormone help to keep our bodies lean. As we age, declining growth hormone supplies are a key factor that contributes to less muscle mass and greater fat storage.

Two amino acids and potassium in goji berries help our bodies to produce more growth hormone.

L-arginine: Research has shown that this amino acid stimulates significantly higher levels of growth hormone in the blood than a placebo.
L-glutamine: In addition to promoting growth hormone production, the amino acid enhances the production of lean muscle tissue.
Potassium: The mineral is essential for normal function of the pituitary gland, which produces growth hormone.

Counteracting Fat Storage

Stress plays a pivotal role in fat storage. Because goji berries can help to alleviate stress, they can prevent a series of effects that lead to weight gain. When we are under stress, our adrenal glands produce too much of the "fight or flight" hormone, cortisol. Excess levels of cortisol prompt weight gain by:

Telling our bodies to hang on to stored fat
Increasing cravings for sugary, high-fat foods
Directing food calories to be stored as fat, rather than being burned for energy
Stopping the secretion of growth hormone
Exhausting the adrenal glands, causing fatigue and encouraging overeating in an effort to replenish energy

As an adaptogen, goji berries can reduce the impact of stressful circumstances in our daily lives, thereby lowering unhealthy levels of cortisol and enabling us to burn body fat.

Supporting Regular Exercise

Successful and permanent weight loss requires regular physical activity. A few years ago, a study of 4,000 people in the National Weight Loss Registry found that they had lost an average of 66 pounds and kept it off for more than 5 years. Nine out of ten successful losers spent between an hour and 90 minutes daily doing moderate-to-intense exercise. Goji berries help to provide energy for sufficient daily physical activity to lose weight and keep it off.

Improving Physical Performance

As an adaptogen, goji berries enhance the ability to exercise in several ways:

Improving utilization of oxygen
Delaying the onset of fatigue during exercise
Increasing endurance
Increasing stamina
Strengthening the heart
Reducing stress that results from physical exertion
Improving circulation

Aiding Recovery

Goji berries strengthen the glands that are responsible for generating energy, muscle growth and repair -- the adrenals, thymus, thyroid and pituitary. In addition, as an adaptogen, goji berries stimulate the regeneration of muscles.

Polysaccharides help to reduce muscle soreness. The polysaccharides aid in the removal of lactic acid that accumulates in muscles during exertion. Goji berries also help eliminate toxins that are produced during exercise by supporting the liver and protecting it from damage resulting from the extreme demands of intense exercise.

The Verdict

When considering goji berries, it's important to be careful of the hype. Health food, herbal medicine and natural, exotic remedies have become part of the global marketplace in recent years, with marketers often searching for a food or substance that will make consumers believe they're getting all three. For example, as you may recall, 2006 was the year of the pomegranate. Mangosteen, which is actually unrelated to mango, was also a popular fruit. Found in Southeast Asia, mangosteen is used in drinks like XanGo™, which marketers claimed has an extraordinarily high amount of antioxidants and cancer-fighting abilities. Sound familiar? In the past, aloe vera, gingko biloba and ginseng have also been trumpeted as miracle remedies.

Because of the way that some of these plants and fruits have caught on in the past, companies will resort to hyperbole when explaining their products' virtues. One Web site calls goji the " hallelujah berry." Others relate the story of a Chinese man named Li Qing Yuen, who allegedly lived to be 252 years old, and owed his longevity to goji berries. As previously stated, many companies claim that their goji berry products fight cancer, but others also mention cures for diabetes, glaucoma, diminished production of human growth hormone, sexual dysfunction and more. None of these "cures" have been proven.

Some companies have been warned by the FDA for marketing their goji berry products as "intended to prevent, diagnose, mitigate, treat, or cure disease" [ref]. According to the law, making such claims causes the products in question to fall under the category of drugs and subject to FDA approval. The FDA writes:

FDA is aware that Internet distributors may not know that the products they offer are regulated as drugs or that these drugs are not in compliance with the law. Many of these products may be legally marked as dietary supplements if claims about diagnosis, cure, mitigation, treatment, or prevention are removed from the promotional materials and the products otherwise comply with all applicable provisions of the Act and FDA regulations [ref].

Another factor to keep in mind regarding goji berries is the price. Usually these products aren't cheap. A 32-ounce bottle of goji juice is at least $13. A 16-ounce package of dried goji berries is $15 to $22. A product called "Yogi Tea Green Tea Goji Berry Daily Energy Tonic" is $4.49 for 16 tea bags -- much more expensive than other green teas. You also might not be getting what you want: many juices that carry the name goji juice are actually a small amount of goji juice mixed with many other juices.

So are goji berries a good buy? They're certainly healthy and can be a fun, new food to try. Along with a balanced diet and exercise, they can be a good part of a healthy lifestyle -- just don't expect them to cure cancer or replace a visit to the doctor. And when eyeing goji berries in the supermarket or trying them for yourself, don't forget about what may be the most important question of all: how do they taste? That is something only you can decide for yourself.

Goji Berry Vitamina C