Our study reported that Ramadan fasting can decrease body fat without the loss of protein body mass. This could be significant for addressing the safety and benefit of Ramadan fasting and could be considered a rule of fasting for a patient with a metabolic disturbance, i.e. diabetic patients.
A comparison of our results with those of other studies is presented in
Table 3. Our study showed Ramadan fasting decreased body weight, consistent with the findings of other studies (
5,
6,
8,
10,
19,
20). A notable result is that weight loss was not associated with the decrease in calorie intake. The insignificance of calorie intake during Ramadan was also observed by Norouzy et al. (
8) and Sadiya et al. (
5) A plausible explanation for the weight loss during Ramadan is the increase in energy requirement due to an increase in physical activity or basal metabolism. During Ramadan, there are additional obligatory observances besides fasting. These obligatory observances include night prayer and reading the Quran, which could increase the observants’ energy requirements. Sleeping patterns also change during Ramadan (
15). Bahijri et al. (
15) observed that the cortisol circadian rhythm was abolished and that circulating insulin levels and the homeostasis model assessment insulin resistance equation (HOMA-IR) index increased during Ramadan fasting. This pattern is typical of conditions associated with chronic stress, with the level of catecholamine during stress usually increasing. The increase in catecholamine level during Ramadan fasting could influence the body’s basal metabolism. However, further research should be conducted on this theory.
| Parameters | Present Study | Norouzy et al. (8) | Hosseini et al. (19) | Faris et al. (20) | Sadiya et al. (5) |
|---|
| Measurement | | | | | |
| First | 1st day | A week before | A week before | A week before | A week before |
| Second | 28th day | A week after | A week after | 22nd day | Fourth week |
| No. of subjects | 43 | 82 | 15 | 50 | 19 |
| Male | 7 | 31 | – | 23 | 5 |
| Female | 36 | 51 | 15 | 27 | 14 |
| Healthy subjects | Yes | Yes | Yes | Yes | No |
| Ages | 22 – 54 | 18 – 37 | 20–45 | 18 – 51 | 37.1 ± 12.5 |
| Weight changes | Decreased | Decreased | Decreased | Decreased | Decreased |
| BMI changes | Decreased | Decreased | Decreased | No change | Decreased |
| Fat changes | Decreased | Decreased | No change | No change | No change |
| Protein changes | No change | - | No change | - | No change |
| Mineral changes | Decreased | - | No change | - | - |
| Water changes | Decreased | - | No change | - | No change |
| Intake | No change | No change | - | - | No change |
| Weight rebound | Yes | - | - | Yes | - |
Our study found that the proportion of weight loss did not differ across gender and profession. The study by Norouzy et al. (
8) and a meta-analysis by Kul et al. (
6) found males to have higher weight loss than females did during Ramadan. Weight loss can be the result of physical activity. In our subjects, relatively no differences existed in physical activity across neither profession nor gender in our medical staff members. However, because the number of subjects was limited, further study is required to validate this finding.
While weight loss during Ramadan fasting was consistently found across subjects, the body composition results varied. The insignificance of protein mass loss in our study was consistent with the findings of Hosseini et al. (
19) and Sadiya et al., (
5) but the results for fat, mineral and total body water changes varied. In our study, these three body components significantly decreased during Ramadan fasting, with the fat component contributing the greatest proportion of weight loss. Hosseini et al. (
19) and Sadiya et al. (
5) reported a significant decrease only in body fat. These findings suggest that in Ramadan fasting, the body metabolism is switched to lipolysis but not gluconeogenesis. Gustaviani et al. (
21) also found that Ramadan fasting did not cause the formation of β-hydroxybutirate, the product of lipolysis in well-controlled diabetic patients. A decrease in body fat, especially visceral body fat, is beneficial. An increase in abdominal adipose tissue confers an independent risk of cardiometabolic and cerebrovascular disease (
22,
23). In this study, we found a non-significant decrease in WHR.
The effect of Ramadan fasting on decreased weight and body fat was small and temporary. In our study, the weight and body fat were regained 4-5 weeks after Ramadan (
7,
20). Other studies have also found the weight loss during Ramadan fasting to be regained shortly after Ramadan. The temporary effect of Ramadan on body weight and composition means the benefits of Ramadan fasting do not last long.
In line with our study, there is evidence to suggest that Ramadan fasting decreases several risk factors and improves biological parameters. However, no studies have yet reported the long-term or clinically significant effects of Ramadan fasting on health status in general or on the reduction of metabolic and cardiovascular diseases. A systematic review performed by Salim et al. (
14) noted that the incidence of acute cardiac illness during Ramadan fasting was similar to that on non-fasting days, with BMI, lipid profile and blood pressure showing significant improvement in normal healthy subjects, patients with stable cardiac illness, metabolic syndrome, dyslipidemia and hypertension. Unfortunately, there is no evidence to suggest that Ramadan fasting could actually decrease the metabolic or macro-vascular diseases. This could be caused by the temporary nature of the Ramadan effect.
Another form of fasting in Islam is Sunnah fasting, which is held every Monday and Thursday throughout the year. The combination of Ramadan and Sunnah fasting may be able to extend the beneficial effect of religious fasting. Further research is needed to determine the effect of the implementation of such fasting on body weight and general health.
This study discusses the important role of fasting and its effectiveness in reducing weight, BMI, body fat and body water but not protein body mass. Our report could be significant for addressing the safety and benefit of Ramadan fasting. This study can also serve as a reference for practitioners and people who want to follow the rule of Ramadan fasting in reducing weight and also for those who have a metabolism disorder. The limitation of the study is the small number of subjects, which cannot fully represent the general population. Moreover, the proportion of male and female subjects is unbalanced, so this study did not compare body composition between male and female participants.
Ramadan fasting resulted in weight loss even it was only a temporary effect, as the weight was quickly regained within one month after fasting. The catabolism state, which is related to protein loss was not triggered during Ramadan fasting. Ramadan fasting seems to be useful for people who want to reduce their weight, but they need to maintain daily meal and physical activities to prevent weight gain. Further research is needed to evaluate the effects of weight loss during Ramadan fasting in healthy individuals.