Acidity or a burning sensation in the food pipe is a common problem of the digestive tract. Both acid reflux and GERD (Gastro-esophageal reflux disease) can occur, which have similar symptoms. Reflux is termed as GERD when semi digested food from the stomach backflows into the oesophagus at least once a week. The person may also experience other symptoms of reflux on a weekly basis.
The symptoms include a burning sensation in the stomach, chest or food pipe, nausea, difficulty swallowing and regurgitation.
How reflux happens
When food is eaten, it passes through the oesophagus into the stomach. A sphincter present (called the lower oesophageal sphincter- LES) acts like a gate keeper and closes to prevent the back flow of the stomach contents. However, sometimes this muscle relaxes causing the food contents mixed with digestive acids to flow back into the oesophagus resulting in a burning sensation. The muscle relaxation is thought to be due to various factors such as- lack of physical activity (sedentary lifestyle), stress, erratic eating patterns, sleep patterns and body weight (especially abdominal adiposity). When this happens, the acids can also damage the mucous membrane of the sphincter leading to inflammation. Research has shown that these acids also affect the lungs and the teeth due to their acidic content and cause erosion of dental enamel. (Ranjitkar S, Kaidonis JA, Smales RJ. Gastroesophageal Reflux Disease and Tooth Erosion. International Journal of Dentistry. 2012;2012:479850. doi:10.1155/2012/479850.)
Pregnant women may experience reflux due to the increased abdominal pressure caused by the foetus. But this usually subsides after delivery and is only temporary. Lifestyle modifications have found to be beneficial in these cases.
Overall, lifestyle is very important to prevent these symptoms and healthy changes can have immense benefits.
Weight:
Excess abdominal fat puts pressure on the LES and tends to relax the sphincter aggravating the condition. Studies have been done to establish the role that obesity plays, though some have been conflicting, overall it was found that controlling body weight with focus on abdominal adiposity would help reduce complications. Population studies have shown a positive directly proportional , significant association between BMI and reflux symptoms. (Nocon M et al. Association of body mass index with heartburn, regurgitation and esophagitis: results of the Progression of Gastroesophageal Reflux Disease study. J Gastroenterol Hepatol. 2007;22:1728-1731.)
Drugs (over the counter and prescription):
High blood pressure drugs like alpha blockers, calcium channel blockers, and nitrate vasodilators can alter the LES tone (these cause relaxation of the sphincter), resulting in inflammation and slow digestion causing a backflow of the stomach contents. Drugs for anxiety, depression, nausea, asthma, sedatives, oestrogen replacements and Parkinson's disease can have similar effects.
Medications that cause inflammation (Inflammatory eye reactions) include Biphosphonates (which are used to treat osteoporosis), potassium supplements, and antibiotics, heart medications like (Quinidine) and potassium supplements. In particular, NSAIDS (Non-steroidal anti-inflammatory drugs) are known to cause inflammation.
Diet:
Nutritional research to date has shown associations rather than causes between diet and acidity. In clinical practise, patients most often note symptoms post prandially, resulting in advice to patients to avoid ‘suspect' foods. (DeVault KR, Castell DO. Updated guidelines for the diagnosis and treatment of gastroesophageal reflux disease. Am J Gastroenterol. 2005;100:190-200.)
Studies have used dietary questionnaires to estimate the average food consumption and endoscopies to assess severity of symptoms. (El-Serag HB, Satia JA, Rabeneck L. Dietary intake and the risk of gastro-oesophageal reflux disease: a cross sectional study in volunteers. Gut. 2005;54:11-17) and (Shapiro M, Green C, Bautista JM, Dekel R, Risner-Adler S, Whitacre R, Graver E, Fass R. Assessment of dietary nutrients that influence perception of intra-oesophageal acid reflux events in patients with gastro-oesophageal reflux disease. Aliment Pharmacol Ther. 2007;25:93-101.)
The consensus has agreed that a diet low in dietary fat and high in fiber is beneficial. There was a positive association with a diet high in fat and acidity symptoms. This was also directly related to the BMI of the individual and was statistically significant in those who were overweight. The study by Shapiro et al., showed that diets rich in "cholesterol, saturated fatty acids and a higher percentage of calories from fats was significantly associated with an increased likelihood of having reflux events."
Other studies have placed a higher importance on BMI rather than dietary fats as they did not find a causal relationship between dietary fats and reflux. Some studies have researched specific foods known to cause acidity such as coffee and alcohol. Shapiro et al, not only confirmed these results, but also documented that alcohol was associated with a reduced perception of intra-oesophageal acid reflux events. With regards to coffee it was found that, "coffee consumption is lower in subjects with reflux symptoms. However, the latter result might reflect avoidance of coffee by those who suffer from reflux because the beverage aggravates symptoms."
In spite of the variations in evidence, dietary and lifestyle interventions are recommended initially to help reduce symptoms, the dietary suggestions are based on the post prandial studies and their relationship between foods ingested and symptoms (intolerances) experienced.
Fat- Medium and long chain fatty acids were shown to delay gastric emptying. This causes pressure on the stomach which leads to reflux.
Other ‘problem' foods include: Coffee and alcohol (the effects are documented), chocolate, mint, processed foods, fast/junk food and deep fried foods, processed meats, roasted foods (like roasted coffee beans, which contain protein which causes excess secretion of stomach acids), foods too hot or too cold and spicy foods. Those who ate large and / or irregularly timed meals also experienced acidity and heartburn. Grains, sugars, starchy foods and dairy were also reported to cause discomfort in some subjects.
Tips for controlling acidity:
• Have small, frequent, light meals and snacks. Do not overeat, but chew your food slowly and eat portions that keep you satisfied. A vegetarian, plant based diet may be recommended. You can contact a qualified Dietitian who can help you with a customized meal plan.
• Avoid smoking! Studies have been done which show strong associations between cigarette smoking and acidity. Smoking makes the smooth muscle of the LES relax. It also decreases salivary bicarbonate secretion, thus reducing the physiological neutralizing effect of saliva on intra-esophageal acid and prolong acid clearance. (Trudgill NJ et al., Impact of smoking cessation on salivary function in healthy volunteers. Scand J Gastroenterol. 1998;33:568-571.)
• Stay free from stress and stressful situations especially while eating. Meal times should be relaxed and enjoyable. It would also help to stick to a regular time for meals. Do not watch TV or be involved in any other activity while eating.
• Have an early and light dinner (at least 1 ½ to 2 hours) before your bedtime. Lying down immediately after a meal can aggravate symptoms.
• When you sleep, elevate the head of the bed 3-4 inches.
• Discuss any drugs or medicines that you are using with your doctor and ask if replacements are available to prevent acidity.
• If acidity is severe, your doctor may prescribe an alginate or antacid (these contain calcium or magnesium to neutralize acidity and burning).
• As far as possible diet and lifestyle changes are best. Long term use of prescription drugs can lead to nutritional deficiencies, diarrhoea, increased risk of fractures and infections.
• Being well hydrated is also important. Not drinking enough water can result in heartburn. Water helps neutralize the digestive acids. However, it is also important that meals have good portion control. Having a large meal and then drinking water can make the stomach feel heavy and bloated. In this case, drinking water does not have any benefits.