Israel's health ministry said that eight people reported liver problems over a year and a half, five of whom had consumed Herbalife's Sesame Herb product, a fibre supplement said to aid in digestion.
The company said in a statement that it has "temporarily stopped the marketing" of the supplement that is only sold in Israel.
The Los Angeles-based company added: "At this stage, no causal link has been proven between consumption of nutritional supplements and liver function abnormalities in these people."
Herbalife has sent doctors to Israel to review the cases.
Dr Mario Rosenberg, a member of the firm's medical and scientific advisory boards, also chief of gastroenterology at Cedar-Sinai Medical Center in Los Angeles, added: "Further, there are numerous possible explanations that relate to either products or patient conditions. We need to do an evidence-based review."
Herbalife is one of the largest network marketing companies in the world, with net sales of around $1.2 billion in 2003. It sells weight management, nutritional supplement and personal care products through distributors in more than 59 countries.
The Sesame Herb product contains the following ingredients: tricalcium phosphate, calcium carbonate, black sesame seed, mung bean, microcrystalline cellulose, corn starch, silicon dioxide, lecithin, garlic powder, dextrin, cider vinegar, chickweed herb powder, ginger root powder, couch grass powder, Echinacea extract, black walnut leaf powder, fennelseed powder, dandelion root, parsley, papaya fruit, kelp powder, dextrose, sodium citrate, maltodextrin, dicalcium phosphate and lactose.