Obesity and Heartburn – How are they Related?

Heartburn is a painful burning sensation in the chest, occurring due to the reflux of acid from the stomach in the oesophagus.

The lower oesophageal sphincter muscle or the LES, which is supposed to guard the entry of the stomach, relaxes and allows this reflux of acid, causing heartburn.

The main reasons for relaxation of the LES and heartburn is poor diet, obesity and poor lifestyle, however, there can be other pathological reasons too. Ignorance of the symptoms of heartburn can lead to its chronic form called gastro oesophageal reflux disease .

Obesity and Heartburn

Several food items triggering heartburn is a common knowledge, but what is not commonly known is that obesity is a higher risk factor for induction of heartburn and development of severe GERD. Not just obesity but fluctuation in weight, ultimately increasing the BMI can trigger heartburn, according to a study. These small changes in the weight can increase the severity of the disease too, not just induce it. 

Obesity and overweight are the two independent factors involved in development of GERD. Studies have proved that overweight subjects (BMI = 25-30) and obese subjects (BMI>30) are at a higher risk of getting severe heartburns or GERD as compared to subjects with healthy weight. Also, spicy food, fatty food and other heartburn inducing meals had no role to play in development of reflux symptoms in obese or overweight subjects .

Another study on the frequency of heartburns in obese patients demonstrated that those who had higher body mass index developed heartburns more frequently, even on a healthy diet than those who had heartburns due to poor diet but were not obese.

This directly proves that diet is a more secondary factor in developing heartburns and promoting it to a more chronic form as compared to body mass index which directly affects acid refluxes and its severity .

Obesity in women and heartburns

A study has revealed that both obesity and estrogen work together to develop heartburn and increase its severity. The association between body mass and gastro oesophageal reflux is stronger in women, especially those nearing menopause.

In western societies, those women going through menopause who undergo hormone therapy develop more incidences of GERD then the normal females or men, suggesting the role of female hormones in conjunction with body mass to develop acid reflux . 

Gastro oesophageal pressure gradient in obese patients

Stomach pressure plays an important role in development of heartburn. The gastro oesophageal pressure gradient (GEPG) develops in the oesophagus and regulates the opening of the LES. The LES pressure (LESP), which should be high to keep the muscle from allowing the reflux, in turn depends on the gastro oesophageal pressure gradient. The ratio of GEPG to LESP is unity in healthy subjects. 

However, it was found that the GEPG/LESP in obese patients was significantly greater than unity, changing the pressure gradient of oesophagus and the stomach, Obesity and weight lossconsequently opening passage which is guarded by the LES.

This leads to reflux of acid back in the oesophagus, causing heartburns. The LES relaxes due to poor diet, but even if the diet is healthy in obese subjects and the LESP is normal, the fat deposition around the abdomen increase the GEPG leading to pressure changes and acid reflux .

This also suggests that those heartburn patients with a slightly overweight body, especially with the fat in the abdominal area are more likely to develop heartburn symptoms than those with fat in any other part of the body except the abdomen.

Gastric and Oesophageal emptying in obesity

Stomach emptying time is very important factor in governing the frequency of acid refluxes. If the food is not digested properly due to various factors including obesity, it will remain in the stomach for a longer time until it is fully broken down.

This increase in the time of emptying of stomach increases the risk factor of reflux of acid and stomach contents into the oesophagus sue to sphincter muscle relaxation and increased acid production. independent studies have shown that obesity positively increases the gastric emptying time period which consequently increases the incidences of heartburns .

Lower oesophageal sphincter pressure in obesity

It is well documented that gastro oesophageal pressure gradient is disturbed in obesity which directly affects the lower oesophageal sphincter pressure. Although the relaxation of the sphincter muscle is driven by certain food items and the GEPG, the abdominal fat can also directly affect the LES pressure, leading to its opening and causing acid reflux.

Thus it is important to get rid of the fat in the body especially in the abdominal area which causes more exacerbation of the symptoms of heartburn , .

Gastric Banding for weight loss and reduction of heartburn

Gastric banding or lap banding is a laparoscopic surgical procedure of placing an adjustable silicone band around the top portion of the stomach to reduce consumption of food and reduce obesity . This surgery is usually done to ameliorate the symptoms of heartburn in obese patients. Studies have shown that placement of Lap Band has direct effect on reduction of heartburns and severe GERD, thereby proving the correlation of weight with acid refluxes . 

Another bariatric surgery (surgical weight loss) known as Roux-en-Y gastric bypass (RYGBP) is shown to be even more effective than lap banding. Lap banding can sometimes not be effective in preventing acid refluxes and increasing the oesophageal motility for better passage of food in the stomach, but RYGBP has been shown to be a promising method for reduction of obesity, consequently reducing the incidences of severe heartburn in morbidly obese patients (BMI>40) .

Weight loss as first line of management of heartburn

Despise the paucity and discrepancy between researchers and clinically published trials, weight loss is employed as a primary or first line of treatment for the management of heartburns. Even as little as 10% reductions in weight in severely obese patients has been shown to significantly improve the heartburn cases by reduction in both frequency and severity of acid reflux . 

Weight loss and heartburn reduction methods with precautions

The most common means of reducing weight for amelioration of heartburns is by reducing calorie intake and increasing fibre in the diet for improvement in digestion and avoiding large meals especially in the evenings, apart from a little exercise like walking after eating. This greatly helps in reducing weight especially heartburns associated with obesity.

However, if a non obese person is developing heartburns, it is not advisable to reduce more weight. Also, sudden weight loss of excessive weight loss can be really harmful for the body and thus should be avoided. The best means to lose weight is to consult with a practicing dietician for a proper balanced diet and regular exercise under the supervision of an expert.

This would not only keep the weight in check but also allay heartburns up to 100 percent .

Summary

Obesity has come up to be a leading factor in exacerbation of heartburn incidences and development of severe GERD. Keeping the weight in check for healthy people helps in avoiding heartburns in future and reducing weight preferably by controlling the diet, regular exercise and avoiding heavy meals at night is the best way to reduce heartburns.

For morbidly obese patients, surgical weight loss has been proven beneficial to reduce heartburns but every medical practice can have its side effects and thus natural methods are advised to be employed as a first line of treatment for management of acid refluxes.