The Therapeutic Effects of Camel Milk

Diabetes

Presence of insulin in nanoparticles or an insulin-like substance in camel milk are theories that have been proposed to explain the traditional belief that consumption of camel milk helps prevent and control diabetes. ⁵ The therapeutic effect of camel milk given to animals with artificially induced diabetes was investigated in 4 studies ^{11 –14} (Table 1). Khan et al ²⁰ conducted a randomized controlled trial to assess the effect of camel milk on rats with streptozocin-induced diabetes. After 30 days, they found that rats with diabetes had a 24.8% decrease in weight compared with healthy controls, but camel milk increased body weight to near normal. They also observed a significant increase in fasting plasma glucose (FPG) in diabetic rats compared with controls and lower FPG in diabetic rats given camel milk. However, FPG was still significantly higher in the camel milk group than the healthy control group and the group treated with insulin. Likewise, they found a statistically significant increase in liver enzymes, markers of renal function, and lipid panel in the diabetic group compared with the control group and a decrease in all these parameters with the administration of camel milk.

Similar parameters were assessed in a series of studies by Korish and colleagues. ^12,13 Two of the studies were randomized controlled trials looking at rats with streptozocin-induced diabetes. ^12,13 They found similar trends in body weight, FBG, and fasting insulin as the study by Khan et al. ²⁰ One of the trials also looked at lipid levels and found significantly higher total cholesterol, triglycerides, low-density lipoprotein cholesterol, and very low density lipoprotein cholesterol, and significantly lower high-density lipoprotein in the streptozocin-induced diabetes group. ¹² The levels of randomized controlled trial, triglycerides, low-density lipoprotein cholesterol, and very low density lipoprotein cholesterol decreased when camel milk was given to diabetic and healthy rats, and high-density lipoprotein increased in diabetic rats. This study also assessed the effect of diabetes and camel milk on glucagon-like peptide-1, glucose-dependent insulinotropic peptide, and tumor necrosis factor (TNF)-α and TNF-β. They found a significant increase in all 4 markers in diabetic rats compared with controls, and a decrease in diabetic rats given camel milk compared with those not receiving any. The administration of camel milk to healthy rats did not show any change in these markers compared with controls. The second trial also assessed the effect of camel milk on diabetic nephropathy. ¹³ The authors found that rats with diabetic nephropathy had a significant increase in urine volume, serum urea, serum creatinine, and proteinuria, which were lower in the group treated with camel milk. When camel milk was given to healthy rats, it decreased urine volume compared with the control group but it did not alter any of the other parameters.

The third randomized controlled trial by Korish et al ¹⁴ assessed the effect of camel milk in rats fed either a standard diet or a high-cholesterol diet. Body weight in this study showed the opposite trend compared to the results from Khan et al, ¹¹ highlighting the pathological differences between insulin-dependent diabetes and obesity. The lipid profile and liver enzymes showed a similar trend to the studies by Khan and Korish. ^{11 –13} Investigators also measured serum and liver concentrations of malondialdehyde, catalase, and reduced glutathione as measures of oxidative stress on the liver. They found a statistically significant increase in malondialdehyde and decrease in catalase and reduced glutathione in rats fed a high-fat diet and a return to near-normal levels in those given camel milk.

Cancer

Two studies were identified that investigated the therapeutic effects of camel milk on angiogenesis and cell proliferation, as well as its potential antioxidant and antigenotoxic effects. Alhaider et al ¹⁵ used a randomized approach to determine the extent of vascularization of sponge implants between 3 groups of mice receiving increasing amounts of camel milk and controls (Table 1). Measured by the total amount of hemoglobin present in the tissue after 14 days, the study found higher amounts of camel milk administered (25 and 50 mg/kg/body weight daily) suppressed hemoglobin levels and therefore attenuated vascularization. Levels of vascular endothelial growth factor (VEGF) were also lower in the higher concentration camel milk groups.

The antigenotoxic and anticytotoxic effects of camel milk were investigated in a randomized study using seven groups of 10 mice administered different amounts and combinations of camel milk and cisplatin, as well as a control group ¹⁶ (Table 1). The objective of the study was to assess a potential protective role of camel milk against the genotoxic effects of cisplatin. Cisplatin was administered at subacute doses (0.5 mg/kg) in 3 groups and at acute doses (2.5 mg/kg) in 2 other groups. Camel milk was given orally at an amount of 33 mL/kg. Findings showed significant decreases in the frequency of micronucleated polychromatic erythrocytes and increases in the mitotic index in groups treated with camel milk, which are deemed to be markers of clastogenic and cytotoxic effects of cisplatin. However, the protective effect exhibited by camel milk did not maintain the same levels as control or camel milk alone groups.

Colitis

It was anticipated that the antioxidant and anti-inflammatory properties of camel milk would provide benefit by decreasing the markers of colitis damage. Arab et al ¹⁷ randomized 32 adult rats with and without chemically induced colitis using 2,4,6-trinitrobenzene sulfonic acid (TNBS) to be treated with saline or camel milk (Table 1). The outcomes included anthropomorphic, blinded histological examination, and biochemical markers of colitis. For all results, TNBS-induced rats showed statistically significantly worse results when compared with control groups. Whereas TNBS plus camel milk showed similar outcomes to control in body weight, TNF-α, capsase-3, reduced glutathione, and total antioxidant capacity (TAC) levels but showed statistically worse results in colon weight/length, colon macroscopic damage, area of colonic lesions, myeloperoxidase activity, IL-10, malondialdehyde, and nitric oxide. Despite these results, TNBS plus camel milk showed statistically significantly favorable results when compared with TNBS.

Infections

Two studies were identified relating to the treatment of infections ^18,19 (Table 1). It is hypothesized that the high lactoferrin, an antioxidant and immunomodulator, and immunoglobulin G (IgG) content of camel’s milk could protect the drinker from different infectious agents. In 2013, Cardoso et al ¹⁸ published the effects of camel milk saturated rat food compared with cow milk saturated rat food and controls on survival of mice infected with Salmonella enterica subspecies enterica. The authors found that all the controls groups worked appropriately. Two of the 10 mice treated with cow’s milk and 6 of the 10 mice treated with camel milk survived to 31 days. Camel milk–treated mice showed statistically increased survival compared with the cow’s milk group, but significantly decreased survival compared with mice not infected or those with heat killed Salmonella injections (100% survival). These results suggest improved survival outcome at 31 days in mice treated with camel milk.

A study by Maghraby et al ¹⁹ in 2005 looked at the effects of mature camel milk and camel colostrum on mice infected with Schistosoma mansoni cercariae. Mice were run in with treatment for 45 days prior to infection and followed up at 2, 4, and 6 weeks for the outcomes of total worm burden, IgG levels against soluble worm antigen, glutathione-S-transferase, aspartate transaminase, and alanine transaminase. Only numerical values were given in the results and no statistical tests reported. The authors state that there was no significant change in IgG levels at any time point between the groups without stating a P value.

Other Indications

Two studies identified observed the effects of camel milk in rats with heavy metal induced anemia. ^20,21 One study found that in cadmium-induced mice, camel milk treatment significantly improved anemia and markers of oxidative stress, except for no difference in glutathione levels. ²⁰ The other study investigated aluminum chloride–induced kidney dysfunction, liver dysfunction, and markers of oxidative stress in each organ. ²¹ The camel milk–treated mice had significantly improved endpoints compared with the aluminum toxic group in all biochemical endpoints studied. No conclusions can be drawn between the camel milk–treated groups and controls in these studies as no statistical tests were reported.

It is anticipated that the antioxidant, anti-inflammatory, and antiapoptotic attributes of camel’s milk may help ameliorate damage caused by alcohol induced liver injury. One study examined these results. ²² Rats treated prophylactically (for duration of alcohol ingestion) and therapeutically (half of alcohol ingestion duration) with camel milk showed improved surrogate markers of liver injury when compared with alcohol-treated rats. Therapeutically and prophylactically treating rats resulted in similar outcomes in alanine transaminase, aspartate transaminase, alkaline phosphatase, liver weight to body weight ratio, TNF-α, and caspase-3 serum levels when compared with controls. Camel milk ingestion resulted in higher serum triglycerides in both groups compared with controls. Therapeutically treated rats had no significant difference in TAC levels whereas prophylactically treated rats had statistically lower TAC levels when compared with controls.

Diabetes

A total of 8 studies assessed the effects of camel milk on the prevention and treatment of type 1 and 2 diabetes ^{23 –30} (Table 2). The effect of camel milk compared with cow milk in patients with type 2 diabetes was assessed in an randomized controlled trial conducted by Ejtahed et al. ²³ After 2 months of therapy, they found a statistically significant increase in serum insulin concentration in the camel group and a nonsignificant trend toward increase in the cow milk group. There were no significant changes in any other parameters.

Mohamad et al ²⁴ conducted another randomized controlled trial of 54 patients with type 1 diabetes randomized to receive usual care or usual care plus camel milk. The treatment groups were also compared to a group of 10 healthy patients. ²⁴ After 16 weeks of therapy, they found that the group receiving camel milk had a significantly lower mean HbA1c, daily insulin dose, and FBG. However, this was at the expense of a significantly higher mean body mass index and c-peptide. There was no significant difference in lipid levels or renal function.

Three other studies were identified by Agrawal et al assessing various outcomes of camel milk supplementation in patients with type 1 diabetes through randomized controlled trial ^25,26 and cohort designs. ²⁷ They found a significant reduction in mean daily dose of insulin when camel milk was compared with usual care, ²⁹ added to intensive insulin therapy for 12 months, ²⁷ and for 24 months. ²⁶ Two studies also found a significant decrease in mean blood glucose, ^25,27 and 1 study found a reduction in HbA1c. ²⁵ Comparatively, only 1 study found a significant reduction in mean blood glucose in the usual care group, and none showed a reduction in HbA1c or daily insulin dose. ²⁵ Although camel milk appears to have an effect on lowering blood glucose and decreasing the dose of insulin required, there were no statistical analyses done between the 2 groups (only before and after therapy in each group); therefore, it is difficult to assess the true benefit over usual care.

Agrawal et al ²⁸ also conducted 1 crossover trial in type 2 diabetic patients in order to assess the effect of camel milk versus cow milk on general diabetes monitoring parameters. The outcomes were measured after a 1-month run-in period (education on diet, exercise, and insulin administration), 3 months of initial therapy (camel milk in diabetic patients and cow milk in nondiabetic patients), 1 month washout, and 3 months of the other milk product. They found, in the diabetic patients, that camel milk significantly reduced FBG, HbA1c, blood glucose 2 hours after an oral glucose tolerance test, area under the curve (AUC) glucose, and AUC insulin. All of these markers returned to baseline after the patients were crossed over to cow milk. In the nondiabetic group, there were no statistically significant differences in any parameters after 3 months of cow milk consumption, but after the crossover period, where they received camel milk, there was a statistically significant decrease in HbA1c and triglycerides.

One before-and-after study was conducted by Agrawal et al ²⁹ to assess the outcome of microalbuminuria before and after camel milk supplementation in patients with type 1 diabetes. It was noted that there was a significant decrease in daily insulin dose and microalbuminuria after 6 months of camel milk therapy. However, there was no control group in this study and all the patients were initially entered into a 1-month run-in period in which they received teaching on a standardized diet, exercise regimen, and insulin administration. Therefore, it is unclear if the positive effect they saw on microalbuminuria and daily insulin requirement was a result of the camel milk or of the new lifestyle modifications.

Finally, one study was identified that assessed the benefits of camel milk in preventing diabetes. ³⁰ Agrawal and colleagues had previously identified that the Raica community of northern India, who consume camel milk, had low prevalence of diabetes. Subsequently, they conducted a cross-sectional study to compare the prevalence of impaired fasting glucose (IFG), impaired glucose tolerance (IGT), and overt diabetes mellitus (DM) in 1055 Raica and 1044 non-Raica Indian community consuming and not consuming camel milk. The results show a trend to lower rates of IFG, IGT, and DM independently in the Raica community and in communities consuming camel milk.

Autism

Because of its unique composition, camel milk is being investigated for potential effects of oxidative stress along with therapeutic effects in patients with autism spectrum disorder (ASD). Two studies identified in the search sought to evaluate the effect of camel milk consumption on the clinical outcomes of autism and on oxidative stress markers. Al-Ayadhi et al ³¹ used a randomized, double blind, placebo-controlled approach to determine the effects of raw and boiled camel milk on the Childhood Autism Rating Scale (CARS) and oxidative stress biomarkers including glutathione, superoxide dismutase, and myeloperoxidase (Table 2). Study participants aged 2 to 12 years were randomized into 3 different groups (boiled camel milk, raw camel milk, cow milk [placebo]) and received 500 mL of their respective milk product daily for 14 days. Participants were assessed prior to the introduction of milk into their diet and after receiving the milk product for 14 days. Both raw and boiled camel milk groups had statistically significant reductions in the CARS and oxidative stress markers. In the placebo group, the cow milk intervention did not significantly reduce any measured outcomes. The authors stated that participants were not allowed to add or remove any interventions such as diet plans, supplements, or pharmacotherapies throughout the study period.

In a second study, Bashir et al ³² used a randomized, double blind, placebo-controlled design to assess the effects of camel milk on the CARS assessment and thymus and activation-regulated chemokine (TARC) serum levels (Table 2). Study participants aged 2 to 12 years were randomized to receive boiled or raw camel milk or cow milk 500 mL for 2 weeks. Prior to randomization a baseline CARS evaluation was performed by a child psychiatrist and blood samples were collected at an autism research and treatment center. Findings from this study showed that raw camel milk was associated with significant improvements in the CARS score compared with baseline, while both raw and boiled camel milk were associated with significant decreases in serum levels of TARC. Cow milk was not associated with any significant changes in either measurement. Camel milk in both preparations was generally well tolerated with only irritability and stomach discomfort noted, although the true numbers of children experiencing these adverse effects were not described.

Two recent reports have also been published highlighting the anecdotal benefits of camel milk in children and youth with ASD. Shabo and Yagil ³³ reported that in a population of 4- to 21-year-olds with ASD, the introduction of camel milk into the regular diet was associated with a subjective improvement in behavior and functioning ability. A case report by Adams ³⁴ in 2013 presented a mother’s experience with using camel milk in her autistic son stating improvement after a single ingestion of camel milk through behavioral changes. These beneficial effects were sustained throughout the period of camel milk use but dissipated on cessation of camel milk use.