immune system – Five Star Wellness

The common cold 着凉，伤风

The common cold is an infection of the upper respiratory tract caused by viruses. There are over 200 viruses that can cause the common cold. Most viruses strike 18 to 24 hours after they enter the body and clear up within 7 to 10 days. General good health and hygiene can reduce the risk of coming into contact with these bugs.

Once cold or flu symptoms begin, an increased intake of vitamin C, garlic, echinacea and cinnamon extract can help relieve the severity, duration and symptoms of the common cold and flu. Plenty of rest and lots of fluid and good nutrition is important with a diet rich in vegetables. Avoid raw foods at this time as the digestive system is often impaired.

It is tempting to suppress symptoms such as fever and cough with drugs. Unless it is severe, avoid symptom suppression as it interferes with the body’s natural repair rhythm and may disrupt the healing process.

Possible signs and symptoms

Nose congestion, sore throat, coughing, sneezing, fever, watery eyes, headaches, fatigue and muscular pain.

Possible causes

A compromised immune system susceptible to viral attack.

Applied nutrition

Keep hydrated with purified water. Eat ginger alone or with hot honey.

Supplement	Benefit	Suggested Dosage
Protein	Supplies balanced amounts of nine essential amino acids for healing.	1 scoop, 2x daily
Vitamin C + bioflavonoids	Fights cold viruses, an antioxidant that boosts the immune system.	5 tabs every 4 hours (if temperature is above 38.5°C: 10 tabs)
Multi-carotene	Helps to clear inflamed mucus membranes and strengthens the immune system.	2 tabs daily
B Complex	Heals and reduces stress.	2 tabs, 3x daily
Garlic + licorice	A natural antibiotic and immune system enhancer which fights cold and flu infections.	2 tabs, 3x daily
Echinacea	Helps reduce the severity and duration of the flu.	2 tabs, 3x daily
ClearGuard	Helps balance histamine release and clears stuffy noses in three days or less.	3 tabs, 2x daily

Vitamin D

Overview

Vitamin D is a fat-soluble vitamin that plays a role in many important body functions. It is best known for working with calcium in your body to help build and maintain strong bones. Vitamin D is also involved in regulating the immune system and cells, where it may help prevent cancer.

In children, a vitamin D deficiency can cause rickets, a condition of soft, weak bones. In adults, many people may not be getting enough vitamin D, especially those who work in offices and the elderly. People with dark skin do not absorb sunlight as easily as those with light skin, so their risk of low vitamin D is even higher. One study of childbearing women in the Northern U.S. found that 54% of African-American women and 42% of white women had low levels of vitamin D.

That’s important because researchers are beginning to find that low levels of vitamin D may be linked to other diseases, including breast and colon cancer, prostate cancer, high blood pressure, depression, and obesity. The evidence doesn’t prove that too little vitamin D causes these conditions, but that people with higher levels of vitamin D are less likely to get these diseases.

Uses

Getting the proper amount of vitamin D may help prevent several serious health conditions.

Osteoporosis
Vitamin D helps your body absorb and use calcium, which you need for strong bones. Getting enough vitamin D throughout your life is important, since most bone is formed when you are young. For post-menopausal women who are at higher risk of osteoporosis, taking vitamin D along with calcium supplements can reduce the rate of bone loss, help prevent osteoporosis, and may reduce the risk of fractures.

Other Bone Disorders
Vitamin D protects against rickets and osteomalacia, softening of the bones in adults. Seniors who do not get direct sunlight for at least 45 minutes per week should make sure they get enough vitamin D through food supplements.

Prevention of Falls
People who have low levels of vitamin D are at greater risk of falling, and studies have found that taking a vitamin D supplement (700 – 1000 IU daily) may reduce that risk. In seniors, vitamin D may reduce falls by 22%.

Parathyroid Problems
The four parathyroid glands are located in the neck. They make parathyroid hormone (PTH), which helps the body store and use calcium and phosphorus. Vitamin D is often used to treat disorders of the parathyroid gland.

High Blood Pressure (Hypertension)
In population studies, people with low levels of vitamin D seem to have a high risk of developing high blood pressure than those with higher levels of vitamin D. However, there’s no proof that low levels of vitamin D cause high blood pressure in healthy people.

Evidence about vitamin D and blood pressure has been mixed. When people with kidney disease or an overactive parathyroid gland (hyperparathyroidism) develop high blood pressure, low levels of vitamin D may play a role. But another large study found that taking vitamin D and calcium supplements did not lower blood pressure significantly or reduce the risk of developing high blood pressure in postmenopausal women. If you have high blood pressure, you should follow your optimal health guide’s advice about whether vitamin D might help.

Cancer
There is some evidence that getting enough vitamin D may lower your risk of certain cancers, especially of the colon, breast, prostate, skin, and pancreas. This evidence is based mostly on studies of large groups of people

Some research suggests that postmenopausal women who take calcium and vitamin D supplements may have a lower risk of developing cancer of any kind compared to those who don’t take these supplements.

Seasonal Affective Disorder (SAD)
SAD is a type of depression that happens during the long dark winter months. It is often treated with photo (light) therapy. A few studies suggest that the mood of people with SAD improves when they take vitamin D directly.

Diabetes
Population studies find that people who have lower levels of vitamin D are more likely to develop type 2 diabetes than people who have higher levels of vitamin D. But there is no evidence that taking vitamin D can help prevent or treat type 2 diabetes.

One study found that giving infants doses of 2,000 IU per day of vitamin D during the first year of life may help protect them from developing type 1 diabetes when they are older.

Heart Disease
Population studies suggest that people with low levels of vitamin D have a greater risk of developing heart disease, including heart attack, stroke, and heart failure compared to people with higher levels of vitamin D. Low levels of vitamin D may increase the risk of calcium build-up in the arteries. Calcium build-up is part of the plaque that forms in arteries when you have atherosclerosis and can lead to a heart attack or stroke. Other population studies show that people with lower levels of vitamin D are more likely to have risk factors for heart disease, including high blood pressure, type 2 diabetes, obesity, and high cholesterol.

Obesity
Population studies have found that people who have lower levels of vitamin D are more likely to be obese compared to people with higher levels of vitamin D. One high-quality study also found that postmenopausal women who took 400 IU vitamin D plus 1,000 mg calcium daily for 3 years were less likely to gain weight than those who took placebo, although the weight difference was small. Women who were not getting enough calcium to start with (less than 1,200 mg per day) saw the most benefit.

Overall Mortality
Population studies suggest that people with lower levels of vitamin D have a higher risk of dying from any cause.

Dietary and other natural sources

Vitamin D has been described as a sunshine-dependent vitamin. Some dietary vitamin D2 comes from plants, but the largest contribution to dietary intake of vitamin D is the vitamin D3 in fish liver oils, eggs, milk, and liver. Milk is commonly fortified with 10 µg (400 IU) of vitamin D3 per quart. Extremely high potency (40,000 to 50,000 IU) products—sold as prescription or sometimes over the counter—often consist of vitamin D2. Most vitamin D dietary supplements contain vitamin D3. The conversion of international units to metric weights is extremely simple for both vitamin D2 and D3: 1 µg equals 40 IU; 0.025 µg equals 1 IU.

Vitamin D3 (or D2) from foods, or vitamin supplements is inert and must undergo two hydroxylation reactions in the body for activation. The first occurs in the liver and the second in the kidneys, which converts the vitamin D into calcitrol As calcitriol, vitamin D is fundamentally involved in the formation of bone, and so its deficiency can lead to rickets in children or osteoporotic changes in adults.

Although the vitamin can be synthesised in the body with sufficient exposure to sunlight or another ultraviolet (UV) light source, most people are not exposed to such UV light in consistent and sufficient quantities. No extra vitamin D is required when skin exposure to UV light is ample; but without such exposure, a person is completely dependent on ingested vitamin D.

Although adequate UV light exposure can provide sufficient vitamin D, many elderly persons have limited sunlight exposure, inadequate dietary sources, and a decreased ability to activate vitamin D, making them susceptible to vitamin D deficiency (Gloth et al. 1995; Holick 1999). Elderly people are likely to have substantially increased needs for dietary vitamin D because of their decreased mobility and exposure to sun and decreased activation in the liver and kidneys.

Thus, the nutritional need for dietary vitamin D depends on the biosynthesis in the skin, which in turn is influenced by time of exposure to sunlight, season (sun intensity and clothing), latitude, skin pigmentation, and the use of sunscreens.

Safety Considerations and limits

The formation of vitamin D in the skin is slowed once dietary vitamin D intakes are sufficient and blood levels of the activated forms are high. Therefore, excess exposure to sunlight does not lead to vitamin D toxicity (Holick 1999; Hathcock et al. 2007).

Dietary vitamin D can, however, produce toxic effects when consumed in very large quantities, especially over an extended period of time. Studies have shown that subjects with abnormally high levels of vitamin D intake can suffer from a wide range of signs and symptoms, from dehydration to permanent mineral deposits in soft tissues, including muscle, heart, kidney, and cartilage. Continued intake of toxic levels can have severe and persistent adverse consequences.

The traditional—but not data-based—conservatism of vitamin D recommendations is rapidly being corrected to evidence-based assessments. These assessments indicate that larger amounts are now considered safe for most persons. The Council for Responsible Nutrition recommends upper limits for vitamin D supplementation of 250 µg (4,000 IU) per day.

Beta Carotene

Overview

Beta-carotene is one of many hundreds of food carotenoids. Beta-carotene is the most abundant form of provitamin A (material that can be converted into vitamin A) in fruits and vegetables. It gives yellow and orange fruits their rich colours. Beta carotene is an effective source of vitamin A in both conventional foods and vitamin supplements, and is generally safe.

Beta-carotene is an antioxidant. It protects the body from damaging molecules called free radicals. Free radicals damage cells through a process known as oxidation. Over time, this damage can lead to a number of chronic illnesses. There is good evidence that eating more antioxidants foods helps boost your immune system, protect against free radicals, and may lower your risk of heart disease and cancer.

Studies have shown that people with high intakes of beta-carotene or high blood levels of this nutrient have a reduced risk of various diseases, including cancer and heart disease (van Poppel and Goldbohm 1995). In addition, beta-carotene and some other carotenoids may play an important role in facilitating cell-to-cell communications (Acevedo and Bertran 1995). Because many carcinogens inhibit such cellular communications (Gregus and Klaasen 1996), protection of this activity by dietary substances could be an important function in the protection against cancer.

Dietary Sources

The richest sources of beta-carotene are yellow, orange, and green leafy fruits and vegetables (such as carrots, spinach, lettuce, tomatoes, sweet potatoes, broccoli, cantaloupe, and winter squash). In general, the more intense the colour of the fruit or vegetable, the more beta-carotene it has.

Beta-carotene is fat-soluble, so you should take it with meals containing at least 3 g of fat to ensure absorption.

Limits and safety levels

Extensive data show that beta-carotene supplements of 50 mg every other day (the equivalent to 25 mg per day) can be taken for more than a decade without harm in a large group of mostly nonsmokers (Hennekens et al. 1996). The Council for Responsible Nutrition concludes that an intake of 25 mg per day is acceptable for non-smokers. Skin discolouration may occur with larger amounts, but this effect is harmless and self-correcting with intake reduction.

The only evidence of adverse effects of beta-carotene comes from the ATBC and CARET studies, which involved long-term heavy smokers and asbestos workers. These data suggest a LOAEL of 20 mg per day for smokers or asbestos workers, but disparities between the ATBC and CARET results and other data prevent confident identification of any LOAEL for beta-carotene. Smokers and asbestos workers should first control these health risks, then evaluate whether beta-carotene supplements are necessary.

Sources

University of Maryland Medical Center

Vitamin C

Overview

Vitamin C is a water-soluble vitamin, meaning that your body doesn’t store it and must be replenished each day from food. Interestingly, other mammals such as dogs have the ability to make their own vitamin C.

Vitamin C helps the body make collagen, an important protein used to make skin, cartilage, tendons, ligaments, and blood vessels. Vitamin C is also needed for healing wounds, and for repairing and maintaining bones and teeth.

Vitamin C is a highly effective antioxidant, along with vitamin E, beta-carotene, and many other plant-based nutrients. Antioxidants block some of the damage caused by free radicals, substances that damage DNA. The build-up of free radicals over time contributes to the ageing process and the development of health conditions such as cancer, heart disease, and arthritis.

Serious vitamin C deficiency is rare, although studies suggest that many people have low levels of vitamin C. Smoking or living in polluted environments lowers the amount of vitamin C in the body as it is used to resist damage from the pollution, so smokers and people living in polluted environments need more vitamin C to enjoy the same effects as others living in healthier environs.

Signs of vitamin deficiency include dry and splitting hair; gingivitis (inflammation of the gums) and bleeding gums; rough, dry, scaly skin; decreased wound-healing rate, easy bruising; nosebleeds; and a decreased ability to ward off infection. A severe form of vitamin C deficiency is known as scurvy, a condition that used to be common among seafarers on long ocean voyages.

Low levels of vitamin C have been associated with a number of conditions, including high blood pressure, gallbladder disease, stroke, some cancers, and atherosclerosis (the build-up plaque in blood vessels that can lead to heart attack and stroke). Getting enough vitamin C from your daily diet will reduce the risk of developing some of these conditions.

Vitamin C plays a role in protecting against the following:

Heart Disease

Vitamin C doesn’t lower cholesterol levels or reduce the overall risk of heart attack, but evidence suggests that it helps protect arteries against damage.

Vitamin C, acting as an antioxidant, can slow down the progression of atherosclerosis (hardening of the arteries). It helps prevent damage to low density lipoproteins (LDL, “bad cholesterol”), which builds up as plaque in the arteries and can cause heart attack or stroke. Other studies suggest that vitamin C helps keep arteries flexible, allowing them to withstand higher blood pressure and improve circulation.

In addition, people who have low levels of vitamin C may be more likely to have a heart attack, stroke, or peripheral artery disease, all potential results of having atherosclerosis. Peripheral artery disease is the term used to describe atherosclerosis of the blood vessels to the legs. This can lead to pain when walking, known as intermittent claudication.

High Blood Pressure

Population based studies (which involve observing large groups of people over time) suggest that people who eat foods rich in antioxidants, including vitamin C, have a lower risk of high blood pressure than people who have poorer diets. Eating foods rich in vitamin C is important for your overall health, especially if you are at risk for high blood pressure.

The diet most frequently recommend for treatment and prevention of high blood pressure, known as the DASH (Dietary Approaches to Stop Hypertension) diet, includes lots of fruits and vegetables, which are loaded with antioxidants.

Common Cold

Despite the popular belief that vitamin C can cure the common cold, the scientific evidence doesn’t support the notion. Taking pure vitamin C supplements regularly (not just at the beginning of a cold) produces only a small reduction in the duration of a cold (about 1 day). A whole-food supplement, such as Nutrilite Bio-C tablets derived from acerola cherries are replete with phytonutrients and other nutrients from the cherry fruit which help strengthen the immune system far more than pure ascorbic acid pills.

Cancer

Results of many population based studies (evaluating groups of people over time) suggest that eating foods rich in vitamin C may be associated with lower rates of cancer, including skin cancer, cervical dysplasia (changes to the cervix which may be cancerous or precancerous, picked up by pap smear), and, possibly, breast cancer. These foods also contain many other beneficial nutrients and antioxidants.

If you are undergoing chemotherapy, please let your wellness consultant know.

Osteoarthritis

Vitamin C is essential for the body to make collagen, which is a part of normal cartilage. Cartilage is destroyed in osteoarthritis (OA), putting pressure on bones and joints. In addition, some researchers think that free radicals may also be involved in the destruction of cartilage. Antioxidants such as vitamin C appear to limit the damage caused by free radicals. Evidence shows that people who eat diets rich in vitamin C are less likely to be diagnosed with arthritis.

Taking nonsteroidal anti-inflammatory drugs can lower your levels of vitamin C. If you take these drugs regularly, vitamin C supplementation may be highly beneficial.

Age-related Macular Degeneration

Vitamin C (500 mg) appears to work with other antioxidants, including beta-carotene (15 mg), and vitamin E (400 IU) to protect the eyes against developing macular degeneration (AMD), the leading cause of legal blindness in people over 55 in the United States. The people who seem to benefit are those with advanced AMD. It isn’t known whether this combination of nutrients helps prevent AMD or is beneficial for people with less advanced AMD.

Pre-eclampsia

Some studies suggest that taking vitamin C along with vitamin E may help prevent pre-eclampsia in women who are at high risk. Pre-eclampsia, characterized by high blood pressure and too much protein in the urine, is a common cause of premature births.

Asthma

Studies are mixed when it comes to the effect of vitamin C on asthma. Some show that low levels of vitamin C are more common in people with asthma, leading some researchers to think that low levels of vitamin C might increase the risk for this condition. Other studies seem to show that vitamin C may help reduce symptoms of exercise-induced asthma.

Other

Although the information is limited, studies suggest that vitamin C may also be helpful for:

Improving vision for those with uveitis (an inflammation of the middle part of the eye)
Treating allergy-related conditions, such as asthma, eczema, and hay fever (called allergic rhinitis)
Reducing effects of sun exposure, such as sunburn or redness (called erythema)
Alleviating dry mouth, particularly from antidepressant medications (a common side effect from these drugs)
Healing burns and wounds
Decreasing blood sugar in people with diabetes
Some viral conditions, including mononucleosis

Dietary Sources

Some excellent sources of vitamin C are oranges, green peppers, watermelon, papaya, grapefruit, cantaloupe, strawberries, kiwi, mango, broccoli, tomatoes, Brussels sprouts, cauliflower, cabbage, and citrus juices. Raw and cooked leafy greens (turnip greens, spinach), red and green peppers, canned and fresh tomatoes, potatoes, winter squash, raspberries, blueberries, cranberries, and pineapple are also rich sources of vitamin C.

Vitamin C is sensitive to light, air, and heat, so you’ll get the most vitamin C if you eat fruits and vegetables raw or lightly cooked.

Safety concerns, rumors and limits

Vitamin C has very low toxicity and is not believed to cause serious adverse effects at high intakes. The most common complaints after very high intakes of vitamin C are diarrhea, nausea, abdominal cramps, and other gastrointestinal effects related to the osmotic effect of unabsorbed vitamin C in the intestine (Institute of Medicine [IOM] 2000). Once the excess vitamin is flushed out of the system, the body regains its balance.

Over the years, vitamin C has been a victim of many rumours without scientific corroboration or basis. Authoritative reviews by the Institute of Medicine has found that Vitamin C intake has no relation with respect to the risk of oxalate kidney stones and the destruction of Vitamin B12 in the body. In relation to erosion of dental enamel, high-quality chewable vitamin supplements are buffered against low pH and no not cause dental enamel erosion.

The adverse gastrointestinal effects of very high intakes justify the establishment of a UL at 2,000 mg per day according to the Council for Responsible Nutrition.

Sources

Vitamin C (Ascorbic acid) | University of Maryland Medical Center
Council for Responsible Nutrition