Scientific Response to the ASSAf Report

The report entitled “HIV/AIDS, TB and Nutrition” by a “consensus” study panel of the Academy of Science of South Africa (ASSAf), referred to as the ‘study report’, considers the influence of nutrition on two major disease pandemics affecting South Africa - HIV/AIDS and tuberculosis. It acknowledges the prevalence of a third pandemic namely ‘malnutrition’, which is intricately linked to the other two disease epidemics.

In order to fashion a response to these tripartite epidemics, the study panel reviews the scientific evidence linking nutrition to immunity with specific reference to these chronic conditions and makes recommendations on nutritional policy and practice as it pertains to the management of these pandemics. It also offers a series of recommendations for undertaking well-designed research studies to deal with a situation by which it says it is “frankly appalled” namely “the dearth of reliable and truly informative studies of the nutritional influences/interventions on the course and outcomes of the pandemic chronic diseases addressed in this report”.

The study report sounds like the reaction of Rip Van Winkle after waking up from 40 years of sleep. Its publication at this time must be questioned as politically motivated. In terms of the scientific evidence reviewed in the report, it is nothing new. The evidence linking nutrition to immunity has existed in the literature since the 1960s and the studies evaluating the impact of nutrients on the outcome of HIV/AIDS and TB have been around for a couple of decades. Nutritional researchers and health foundations (including ours) have been aware of this body of knowledge and have repeatedly tried to point out the value of nutritional intervention in the control of chronic diseases over the last decade. It is ironical but gratifying that the Academy of Sciences has finally caught up and embraced the pivotal role of nutrition in the management of chronic disease after having ignored it over several decades. Despite that, the report is highly selective, lacks conviction and ignores citing studies of important nutrients.

Although the study report acknowledges the importance of nutritional support including macro/micronutrient supplementation in health, life-style and drug response, a careful examination shows that it is deficient in several scientific aspects of the interrelationship between nutrition, immunity and infection, consequently diminishing the significance of the full impact of nutritional supplementation on the outcome of pandemic chronic diseases. Further, in its review, the report picks and chooses specific nutrients almost by whim or fiat, ignoring the value of others, thereby introducing bias in its inquiry. These scientific deficiencies and biases diminish the value of the report and tend to mislead many good-willing health professionals in considering micronutrient supplementation for their patients, despite a good record of safety and effectiveness of these food components.

Some specific aspects omitted in this report are discussed below.

1. The ASSAf report ignores basic scientific studies of nutrient effects on HIV

In chapter 4, the report reviews the relationship of nutrients to immunity in HIV infection and TB. However, it completely ignores any discussion of the basic mechanistic studies that have provided the rationale for a role of nutrients in suppressing HIV. Laboratory studies are an essential first step in the discovery and development of new therapies. Even during the development of the first AIDS drug AZT, lab studies preceded clinical trials prior to drug approval.

In this context conventional lab tests employing chronically or acutely HIV-infected cell cultures, have shown that the nutrient - vitamin C (ascorbic acid) was capable of suppressing HIV replication by 99.9% in the infected cell lines (1). A separate study conducted by the same research group provided the mechanism of vitamin C’s anti-HIV action (2) and reported that vitamin C was more effective than AZT in suppressing HIV in chronically or latently infected cells (3). The poor ability of AZT to suppress HIV expression in chronically infected cells was independently observed by another group from the National Institutes of Health (4). Since then, it is a well-recognized fact that although AZT can prevent infection of freshly or acutely infected cells, it has limited action in suppressing virus expression in chronic or latent infection and it is associated with severe damage to normal cells. All these components do not generate detrimental side effects, which accompany any pharmaceutical drug treatments.

Similar to vitamin C, another class of antioxidants called thiols (sulfur-containing compounds) such as the amino acid cysteine, its derivative NAC and alpha- lipoic acid were shown to suppress HIV expression in HIV-infected cells (5-7). Although the ASSAf study report mentions the role of cysteine in the synthesis of the major intracellular antioxidant (glutathione), it essentially ignores all published studies demonstrating the anti-HIV action of the thiol-based antioxidants.

2. The ASSAf report ignores clinical benefits of specific vitamins and thiols

The above observations of vitamins and thiols are not limited to HIV-infected cells in culture. Clinical studies by other researchers published in peer-reviewed scientific journals have documented beneficial effects of vitamin C and other nutrients in HIV-infected persons. Thus, in HIV-infected adults, supplementation with vitamins C and E was shown significantly lower oxidative stress (associated with HIV infection or antiretroviral treatment) and a trend toward reduction in HIV virus level in blood (8). The latter effect was interpreted as ‘non-significant” in the ASSAf report, which is scientifically inaccurate. In a small subgroup of advanced AIDS patients, administration of high-dose vitamin C and NAC (N-acetyl-cysteine) was linked to reduced HIV viral load and improved immune status (9). Additionally, several studies using multivitamins (that include vitamins C and E in the composition) have reported positive benefits in HIV-infected individuals, as reviewed recently (10).

3. The ASSAf report also ignores peer-reviewed studies showing immune-enhancing effects of nutrients in HIV infection

Since the emergence of the AIDS epidemic, both small observational studies and randomized controlled trials have shown the immune restoring potential of single nutrients or nutrient combinations in HIV-infected subjects. These reports have included stabilization of helper T-cell counts by large doses of vitamin C (11), enhancement of CD4 count by alpha lipoic acid (12) and improvement of CD4/CD8 ratios by NAC in the presence (9) or absence of vitamin C (13). More recently, in a prospective, placebo-controlled, double-blinded trial published in J AIDS, a broad-spectrum micronutrient supplement was shown to elevate CD4 count in HIV patients on highly active ARV therapy (14). Despite the publication of these reports in peer-reviewed journals, the Academy panel chose not to include them in their study report, indicating scientific bias.

4. The Academy’s 15-person expert panel “unanimously” supported the view that “specific antiretroviral agents are the only established direct weapon in the treatment of HIV infection itself” without pointing out the known limitations of ARV treatment

Although medical intervention based on antiretroviral (ARV) drugs can lower the HIV viral load, such intervention alone is not a cure for AIDS, as ARV drugs do not correct the underlying malnutrition or nutritional deficiencies prevalent in HIV/AIDS nor do they restore the functionality of the T-lymphocytic immune response, the primary cellular damage in AIDS (10, 15, 16).

Aside from their lack of immune-restoring activity, ARV’s are associated with multiple adverse side effects, which include damage to vital organs such as the liver, blood and bone marrow (17, 18).

Suppression of the immune system in patients undergoing AART has been associated with increased cases of TB infection observed in HIV positive patients (19).

In fact, the antiretroviral drug AZT, which is recommended for reducing HIV transmission in pregnant women and for post-exposure prophylaxis following occupational exposure and sexual assault, is a generalized inhibitor of DNA synthesis, that can suppress the ability of the body to produce red blood cells (anaemia) and white blood cells (myelosupression) as well as cause damage to the heart (20-22).

Additionally, AZT‘s potency is limited to inhibiting only new rounds of viral replication (acute infection), with no effect on suppression of viral expression in chronically or latently infected cells that constitute the major reservoir of silent virus in HIV infection (3, 4).

In a more recent study of malnourished HIV patients in Singapore , it was reported that malnutrition at the time of initiation of ARV treatment was associated with decreased survival, suggesting the need for nutritional supplementation therapy (23).

5. The Academy called for “science-based evidence” to clear up the “confused messages” about the role of nutrition, traditional medicine and alternative remedies in HIV and TB treatment, yet Institutional review boards in South Africa routinely reject nutritional protocols of controlled studies in humans

The Academy condemned what it called “an effectively dual system of approval of medicinal claims” in South Africa , “in which orthodox medicine is evaluated with all the rigor of the regulatory environment, while traditional medicines and alternative therapies continue to claim efficacy without being properly evaluated by the responsible legal and regulatory institutions”. Nutritional researchers are conscientious scientists very much aware of the need to perform clinical tests in humans to obtain scientific evidence before making claims. In fact many of the clinical studies of nutrients conducted in western countries including those cited in the ASSAf report are evidence-based scientific studies that meet above criteria.

Although the Academy feels strongly about the need for institutional review of nutritional studies in South Africa , there is a double standard that operates when it comes to review of pharmaceutical drugs (associated with side effects and expensive) vis-à-vis nutritional formulas (safe and economical). Whereas investigational drug applications are readily approved by institutional committees, nutrient-based applications are not allowed to go forward. A case here in point is the experience of the Rath Health Foundation, Africa . Thus, when the Dr. Rath Foundation Africa had submitted a protocol of a randomized, double-blinded, placebo controlled clinical study of a food supplement to an ethics committee at the Medunsa Medical Center, this protocol was rejected based on one member decision (Dr Du Ploy) without compelling scientific reason and despite eagerness of the physicians at MEDUNSA to conduct the study.

How are researchers to conduct ethically-approved clinical studies of nutrient formulas if ethics committees will only obstruct them? Such obstruction of science-based nutrition research is the underlying cause behind the Academy’s quandary of the “dearth of reliable and truly informative studies of the nutritional influences or interventions on the course and outcomes of the two diseases”.