By Stephen Daniells, 01-Dec-2008
Related topics: Research, Antioxidants, carotenoids, Minerals, Probiotics and prebiotics, Vitamins & premixes
Nutrition and HIV/AIDS are intricately linked. To mark World AIDS Day, NutraIngredients.com looks at the science behind the role of nutrition and nutrients for people living with HIV and/or AIDS.
Infection with HIV can lead to malnutrition, and studies have shown that progression of the disease can be increased by a poor diet. There is clearly great potential for nutrition and nutritional supplements to help improve the lives of millions of people around the world who live with the disease.
While significant research has been done on the antiretroviral therapy (ART), Annabel Kanabus, director of AVERT, an international HIV and AIDS charity based in the UK, told NutraIngredients.com that there has been a real lack of proper trials looking at nutrition and ART, and the interaction between the different ART and nutritional supplements. The situation is further complicated in many developing countries because the use of traditional herbal medicine is often thrown into the mix.
“Unfortunately, our knowledge of the effects of micronutrient supplements among people living with HIV is still rather patchy,” says the charity’s website.
“This is partly because it hasn’t been treated as a major research priority, but also because of difficulties in conducting and interpreting scientific trials.”
According to the World Health Organisation, the number of people living with HIV is at its highest ever – 40.3 million. More than three million people died of AIDS-related illnesses in 2005, with more than 500,000 of these children.
It should be stressed that nutrition is not a replacement for standard antiretroviral drugs, but a potential adjunct or supplement.
A review published in the journal Tropical Medicine & International Health (Friis, 2006, Vol. 11, pp. 1849-1857) reported results of trials involving multivitamins in Tanzania and Thailand, which found positive results regarding the number of deaths, while a trial from Zambia found no benefits.
Furthermore, the US President’s Emergency Plan for AIDS Relief (PEPFAR) currently recommends: “Daily multiple micronutrient supplements (1RDA) for people living with HIV and AIDS, especially pregnant and lactating women and children, according to national guidelines, where dietary assessment indicates inadequate intake of micronutrients from food.”
Beta-carotene and vitamin A
Studies with vitamin A and beta-carotene have yielded mixed results. The WHO currently recommends vitamin A supplements for all young children, including those born to HIV positive mothers, at high risk of vitamin A deficiency, a public health problem in more than 50 per cent of all countries, especially in Africa and South-East Asia, according to the World Health Organisation, and causes blindness in up to 500,000 children each year.
A Canadian study published in the European Journal of Clinical Nutrition (Vol. 60, pp. 1266-1276) reported that a daily high-dose carotenoid supplement restored carotenoid levels and reduced “overall mortality” of AIDS patients, a group at risk of low serum carotenoid concentrations said to be predictor of death.
“Today, when ART is expected to be successful in most cases, natural mixed carotenoid supplementation may be a potential low-cost intervention for those with inadequate response to conventional treatment or lacking access to ART,” wrote the researchers, led by Professor D. William Cameron.
The mechanism behind the apparent benefits is not known, they said, but could be through an interaction with the antiretroviral drugs, which could boost serum concentrations and/or improve the response.
The result of this study, said the researchers, “underscores the importance of further research into the role of micronutrients in AIDS management”.
Bonita de Boer, information officer for AVERT, an international HIV and AIDS charity based in the UK, told NutraIngredients.com in November 2006: “This research is very interesting and provides further support to previous studies demonstrating the benefits of Vitamin A and micronutrient supplementation. It is important to note that the study does not suggest carotenoids should replace antiretroviral drugs, but with further study there may well be a case for introducing them as a supplement alongside standard AIDS treatment.”
Along with vitamin A, AVERT notes that studies with the mineral zinc have reported “interesting results”. A study published in The Lancet (2005, Vol. 366, pp.1862-67) found that a daily supplement of 10mg of zinc sulphate for six months reduced diarrhoea and also improved weight gain.
“Few interventions are available to reduce morbidity in children with HIV-1 infection in resource-poor countries. Although UNAIDS, WHO, and their partners are committed to providing antiretroviral therapy to 3 million people by the end of 2005, antiretroviral therapy and prophylaxis for opportunistic infections are not accessible for many children,” wrote the authors from the Johns Hopkins School of Public Health.
“Programmes to enhance zinc intake in deficient populations with a high prevalence of HIV-1 infection can be implemented without concern for adverse effects on virus replication,” they added.
Previously, concerns about the safety of giving HIV-infected children supplements of zinc had previously been aired based on the fact that the HIV virus requires zinc for its structure and function, and zinc activates lymphocytes that are target cells for HIV-1 replication.
Another promising nutrient is selenium. A study published in the Archives of Internal Medicine (Vol. 167, pp. 148-154) reported that combining selenium supplements with traditional ART produced positive results for controlling the viral load associated with HIV and boosting the numbers of immune cells.
“This study is, to our knowledge, the first double-blind, randomized, placebo-controlled trial in a community-based cohort of HIV-infected men and women to demonstrate that daily supplementation with 200 micrograms of selenium for nine months elevates serum selenium level and suppresses the progression in HIV-1 viral load,” wrote lead author Barry Hurwitz from the University of Miami.
The researchers did not know the mechanism behind the apparent benefits, but suggested that one hypothesis holds that selenium’s antioxidant properties may repair damage done to immune cells by oxygen, which is produced at higher levels in the bodies of patients with HIV.
The researchers called for more research to investigate whether the indirect effect of selenium on CD4 count is limited to mediating the HIV-1 viral load, and what the mechanism(s) driving the effects is.
A new area receiving a lot of attention is the potential to use probiotic supplements to ease the suffering from diarrhoea and nausea amongst people with HIV and AIDS.
A joint study by African and Canadian researchers was reportedly the first to show “the benefits of probiotic yogurt on quality of life of women in Nigeria with HIV/AIDS, and suggests that perhaps a simple fermented food can provide some relief in the management of the AIDS epidemic in Africa,” wrote the authors in the Journal of Clinical Gastroenterology.
Indeed, a recent study by Gregor Reid and his co-workers at the University of Western Ontario appeared to confirm the viability of Lactobacillus rhamnosus GR-1 in yoghurt (Innovative Food Science and Emerging Technologies, doi: 10.1016/j.ifset.2008.10.007).
“We are already have this yoghurt in a community of 350 people in Tanzania, and half of these are HIV,” said Professor Reid.