HIV/AIDS
What is it?
Acquired immune deficiency syndrome (AIDS) is a condition in which there is a serious defect in the immune system, the body's natural defense against disease. This increases susceptibility to opportunistic infections, cancer, nerve disorders, and a variety of other syndromes. Since it was first described in 1981, AIDS has been the cause of much fear and controversy. It is now known to occur as a result of infection with the human immunodeficiency virus (HIV). The World Health Organization (WHO) estimates that some 30 million people worldwide are infected with HIV. More than 90 per cent of these are in developing countries and most do not know that they are infected. In 1997 alone, there were over 2.3 million deaths from the disorder.
HIV infection
HIV was first isolated in the laboratory in 1983, and shown to be the likely cause of AIDS in 1984. The virus is transmitted through certain body fluids including blood, semen, vaginal secretions and breast milk. It is not transmitted by air, saliva, tears or sweat so there is no danger of infection with casual contact.
After HIV enters the body, it becomes incorporated into the genetic material of the body cells and affects the production of a number of different cells of the immune and nervous systems. This eventually reduces the ability of the immune system to fight bacterial, viral and fungal infections, and detect cancerous changes in cells. Nervous system function may also be affected.
Symptoms of hiv/aids
The spectrum of conditions related to AIDS ranges from the presence of HIV with no symptoms to severe immune deficiency with life-threatening secondary infections. It is still unclear how many people infected with HIV will progress to AIDS or how long this process takes. The period between infection with HIV and the onset of AIDS averages ten years in adults in the USA.
As AIDS is not a disease in itself, but rather, an increased susceptibility to infection, the symptoms vary widely. In some cases, HIV infection is followed by flu-like symptoms which may persist for two weeks to a few months. After this, symptoms may disappear for several years. The most common symptoms of AIDS include long-term fatigue, swollen lymph nodes, weight loss, persistent infections, diarrhea, yeast infections and easy bruising.
As the immune system weakens further, an HIV-infected person becomes vulnerable to more serious infections and cancer. Among the more serious disorders are pneumonia, which affects approximately 60 per cent of patients; tuberculosis; and Kaposi's sarcoma, a connective tissue cancer. Even with treatment, most people with AIDS die within a few years of developing infections or cancers that take advantage of their weakened immune systems.
Diagnosis of hiv/aids
HIV diagnosis and laboratory measurements
Infection with the virus is diagnosed by the presence of antibodies to HIV in the blood. These antibodies are usually present in the blood a few weeks after infection. However, in some cases the body may take as long as 35 months to produce detectable antibody levels. Regular testing is recommended for anyone in a high risk group.
While HIV affects a number of different immune cells, it has been found that much of the immune system dysfunction can be explained by the effects of HIV on a certain type of cells called CD4+ lymphocytes (CD4+ T cells). These cells play a crucial role in the immune response, signaling other cells in the immune system to perform their special defensive functions. During the course of infection, the number of these cells progressively declines. The level of CD4+ lymphocytes in the blood has been shown to predict the onset of AIDS symptoms.
A healthy, uninfected person usually has around 800 to 1300 CD4+ lymphocytes per microliter (one millionth of a liter) of blood. Vulnerability to opportunistic infections and cancer increases when an HIV-infected person's CD4+ lymphocyte count falls below 200 to 300 cells per microliter.
Treatment of hiv/aids
As there is no known cure for full-blown AIDS, the aim of therapy is to affect the action of HIV and reduce the immune suppression it causes. With improving treatment, fewer people should develop AIDS and it is possible that HIV infection may one day be a manageable chronic illness.
Managing patients with HIV infection and AIDS is becoming increasingly more complex as new medications and technologies are approved. Recent research shows that therapy which combines more than one type of antiviral drug offers the best chance of managing HIV and AIDS progression. As the majority of AIDS patients die because of opportunistic infections, advances in the prevention and treatment of these has helped to decrease mortality rates in AIDS patients.
Enhancing immune function plays an important role in delaying the onset of AIDS. A healthy diet; nutritional supplements; avoiding smoking, alcohol and caffeine; adequate sleep; and exercise all play an important role in helping the immune system to work well. Stress reduction is also very important. Research has shown that severe life stress increases the risk of early progression of disease in those who are HIV-positive.1
Many HIV-positive people use alternative treatments such as relaxation, touch, spiritual and self help therapies. Herbal medicine, acupuncture, homeopathy and dietary therapies are also popular.
Preventing hiv/aids
Large scale public awareness campaigns have been conducted to inform people about the prevention of HIV infection, particularly those in high risk groups. Higher rates of HIV infection were originally seen in homosexual or bisexual men who had many sex partners, intravenous drug users, heterosexual partners of infected persons, and those who had received blood transfusions. Practising safe sex and avoiding used injection needles are very important in preventing HIV infection.
HIV/AIDS and diet
The progression and physical symptoms of HIV disease are affected by diet. It is very important to eat foods which enhance immune function and to avoid foods and other substances which may cause damage. (See page 422 for more information.)
Medical treatments are more effective in a well-nourished person due to improved drug response and tolerance, and reduced risk of toxicity and adverse reactions. It is important to consult a dietitian or nutritionist knowledgeable in HIV as a lot of general nutrition advice is aimed at people who are overweight, and the needs of an HIV-positive person may be different.
Malnutrition can occur early in HIV infection and nutritional status progressively deteriorates, resulting in weight loss, muscle tissue loss and reduced immune function. The HIV-wasting syndrome may occur because of loss of appetite, increased nutrient needs, altered ability to process nutrients, and decreased absorption. Clinical nutrient deficiencies develop as the disease progresses, and supplements may be very useful. Malnutrition is common in AIDS patients, and those patients in whom it is more severe tend to die sooner.
It is important to eat enough calories to maintain a healthy body weight and to eat enough protein to build muscle and repair any damage that occurs. In those who are infected with HIV but have no signs of the disease, eating a wide variety of healthy foods every day is vital as nutrient and calorie requirements are increased. Diets high in protein, complex carbohydrates and fiber; and low in fat, are usually recommended. Foods which are high in sugar and fat should not replace nutritious foods but can be enjoyed along with these foods and can be useful to help with maintaining or gaining weight. However, large amounts of sugar may suppress immunity and should be avoided.
Food safety can be very important for people with HIV; and handling, cooking and storing food safely are very important to prevent infection. In a 1998 study, New York researchers advised HIV-infected people to boil tap water before drinking. Even at low levels, the water-borne parasite cryptosporidium represents a threat to those with weakened immune systems.2
When and if AIDS develops, specialized dietary approaches are necessary. AIDS sufferers experience various physical disturbances due to the disease or the various medications used to treat it. These include diarrhea, nausea, mouth ulcers, painful swallowing, poor appetite and fatigue. Choosing carefully the types of foods to be eaten and the times and ways to eat them can help deal with these effects.
Vitamins, minerals and hiv/aids
HIV-positive people may be deficient in vitamins A, C, E, B6, B12, folic acid, selenium, zinc and beta carotene. Nutrient deficiencies are often the result of inadequate dietary intake and intestinal malabsorption but it is not well known how individual nutrients are affected by the disease. As any nutrient deficiency leads to lower immune function, it is very likely that deficiencies affect progression to AIDS in HIV-positive people.3
RDA levels are almost certainly inadequate for people with HIV. Optimal dietary intake of all vitamins and minerals is essential and most experts recommend supplements which supply at least 100 per cent of the RDA for all nutrients. It is particularly important to consume adequate amounts of nutrients which strengthen immune function, including antioxidants, B vitamins and trace elements such as selenium and zinc.
Antioxidants
Blood levels of antioxidants are often low in AIDS patients. This leads to increased oxidative and inflammatory damage which can adversely affect the immune system. Increased oxidative damage also affects the nervous system and leads to mental problems. Recent studies have found that HIV patients with the lowest levels of antioxidants may progress to AIDS more quickly than those with high levels. Multiplication of HIV may also be affected by the concentration of antioxidants, and low levels of antioxidants may shorten the time taken for those who are HIV-positive to develop AIDS.4
Vitamin A
Vitamin A deficiency is often seen in HIV-positive people.5 It may be due to metabolic changes associated with HIV infection.6 A 1995 study done on HIV-infected drug users in the US found that there was a higher risk of death in those with vitamin A deficiency.7 Research has shown that development of a deficiency of vitamin A is associated with lower CD4+ lymphocyte counts, and there is some evidence that returning vitamin A levels to normal can increase CD4+ lymphocyte counts.8
Vitamin A deficiency is often seen in HIV-positive pregnant women. This is particularly common in developing countries, although it has been seen in the USA.9 Severe deficiency increases infant mortality and the risk of mother-to-child transmission of HIV. This may be due to impaired immune responses in both mother and baby; an increase in the amount of HIV breast milk and blood; and abnormalities in placental and vaginal tissues.9A 1997 study done on HIV-positive pregnant women in New York State did not find a link between vitamin A levels and transmission of the virus.10
Beta carotene
Beta carotene levels have been shown to be deficient in HIV-positive patients.11,12 Research has shown that large doses of beta carotene may boost immune function. In a Yale University study done in 1995, researchers found that daily supplements of 60 mg beta carotene given to seven AIDS patients for a period of four weeks increased CD4+ lymphocyte cell counts.13 A 1996 double- blind study which looked at the effect of oral beta carotene supplements over a three-month period did not find the same effects. However, both groups in the study were given multivitamin supplements which may have masked any beneficial effect.14 It is possible that natural carotene supplements or increasing intake of carotene-rich foods may be more beneficial than using synthetic beta carotene supplements.15
Vitamin C
Vitamin C supplements are likely to be useful in HIV-positive individuals as they have been shown to boost the immune system and prevent damage to nerves. However, caution should be used with very high doses as they can cause diarrhea. Vitamin C has been shown to inhibit HIV in the laboratory and may also kill HIV-infected cells.16
Vitamin E
Research has shown that many HIV-positive people have a deficiency in blood levels of vitamin E early in the course of their disease. In a 1997 study involving 121 people, researchers showed that these levels decreased significantly over a 12-month period.17
High levels of vitamin E seem to be linked to slower disease progression. In a study published in 1997, researchers at Johns Hopkins University working on the Multicenter AIDS Cohort Study found that those patients with the highest vitamin E intakes had a 35 per cent decrease in risk of progression to AIDS when compared to those in the lowest intake group. The study involved 311 patients followed for a period of nine years.18
B vitamins
Recent research from the US Multicenter AIDS Cohort Study suggests that high intakes of B group vitamin supplements may be associated with improved survival in HIV patients. The average increased survival time was up to 1.3 years. In particular, vitamin B6 intake of more than twice the recommended dietary allowance was associated with longer survival. Vitamin B1 and B2 intakes of more than five times the RDA were also associated with improved survival.19
Vitamin B12
Vitamin B12 is vital for healthy nerve and immune system function. Low blood vitamin B12 levels are common in HIV infection and may help predict those patients in whom the disease will progress most rapidly. Results from the Multicenter AIDS Cohort Study showed that HIV-positive individuals with low serum B12 levels had around four years AIDS-free time whereas those with higher levels were free of the disease for around eight years.20
AIDS patients often show signs of nerve damage, including numbness and tingling in the hands and toes. These symptoms may be due to vitamin B12 deficiency and may lessen after treatment with supplements.21 Even marginal vitamin B12 deficiency is likely to contribute to impairments in mental function. Normalization of vitamin B12 levels seems to improve this.22
Vitamin B6
Vitamin B6 deficiency is common in HIV-infected people. In a 1991 study, University of Miami researchers examined the relationship between deficiency and immune dysfunction. The results showed that while CD4+ and CD8+ cell numbers were not be affected, other measures of immune system function were.23
Selenium
As part of the antioxidant enzyme, glutathione peroxidase, selenium is necessary to help prevent oxidative damage. Levels of this enzyme have been shown to be low in some HIV-positive patients which may increase immune suppression and nerve damage. In a 1997 study done in Germany, blood serum selenium levels were determined in 104 HIV-positive patients at various disease stages. Results showed that both selenium levels and glutathione peroxidase activity in hospitalized AIDS patients were significantly lower compared to healthy subjects and patients with no symptoms.24 Low selenium levels appear to be associated with low CD4+ lymphocyte counts25 and with higher death rates in AIDS patients.26 The results of a 1997 study suggest that deaths from AIDS are higher in areas where soil selenium is low.27
Iron
Anemia is often seen in HIV-positive people, but why this happens is not well understood. Iron deficiency may be associated with reduced immune response in HIV-positive people. However, as HIV disease progresses, body iron stores increase. This enhances oxidative damage, impairs the function of the immune system, and directly promotes the growth of micro-organisms. Some experts believe that reducing the amount of iron in the diet may help minimize the adverse effects of excess iron.28
Zinc
Zinc is probably the most important mineral for immune function. It strengthens the immune system, is vital for cell-mediated immunity, and acts as an antiviral agent. It is also necessary for transport of other nutrients such as vitamin A. The antioxidant enzyme, copper-zinc superoxide dismutase, has been shown in laboratory experiments to inhibit the replication of HIV.29
AIDS patients may suffer from zinc deficiency, which may adversely affect immune function. In a 1995 Italian study, zinc sulfate supplements (200 mg per day for 30 days) were given to patients receiving the medication, azathioprine (AZT). Results showed stabilization in body weight and increases in CD4+ lymphocytes and the immune stimulating hormone levels.30
Low zinc levels have been shown to increase the risk of opportunistic infection in AIDS patients. In a recent study, researchers at the San Francisco General Hospital measured zinc levels in 228 patients with AIDS. They found that those with zinc deficiency had a significantly higher incidence of bacterial infections than did patients with normal zinc levels.31 The frequency of some opportunistic infections was also reduced after zinc supplementation.
Herbal medicine and hiv/aids
There are many herbal medicines which have demonstrated antiviral effects and/or stimulatory effects on the immune system. Some of these and compounds extracted from them have been used to treat those with HIV/AIDS. These include cat's claw (Uncaria tomentosa), echinacea (Echinacea purpurea), ginseng (Panax ginseng), St John's wort (Hypericum perforatum), reishi and shiitake mushrooms, licorice (Glycyrrhiza glabra), turmeric (Curcuma longa), astragalus (Astragalus membranaceous), aloe vera (Aloe vera) and mistletoe (Viscum album). Many patients have also used traditional Chinese herbal treatments.