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In this article we look at what happens if you eat too much or too little and how it may affect those susceptible to acid reflux, hyperacidity and heartburn. What it all comes down to is stomach acid: how much we have, and how it’s behaving. But first let's consider why we have acid in our stomachs in the first place.

The Role of Stomach acid

Your stomach contains an acid known as hydrochloric acid, which has three main functions:1

  • It helps to kill microorganisms that may be in our food
  • It helps the conversion of a chemical called pepsinogen into the active enzyme pepsin
  • It affects the proteins in the food you eat by denaturing them, or causing them to unfold, so that they can be more easily broken down by pepsin into the vital nutrients your body needs.

It would appear that stomach acid is an incredibly useful feature of the body, so why can it cause some people so many problems including stomach pain ? One of the biggest complaints concerning stomach acid, occurs when it leaves your stomach by passing upwards into the oesophagus (gullet or food pipe) –  resulting in heartburn.

Why does stomach acid cause heartburn?

The lining of your oesophagus is not designed to withstand the effect of stomach acid in the same way as your stomach lining does. So if stomach acid comes into contact with the oesophageal lining, by passing upwards through the ring of muscle (sphincter) around the base of the oesophagus, a pain or a burning sensation can result. However, the amount of acid and the length of time it is in contact with the lining are the factors influencing whether you actually get heartburn or not. Prolonged or consistent can cause hyperacidity with is imbalance between the acid secreting mechanism of the stomach and proximal intestine and the protective mechanisms that ensure their safety

What happens when you eat too much?

Eating too much food can result in acid reflux and heartburn in three ways:

  • The volume of the stomach contents is increased, causing extra pressure. This can have an effect on the muscle at the base of the oesophagus, forcing the stomach contents –

including the acid – through the opening of the stomach and into the oesophagus.

  • Food stimulates the stomach to produce acid. As a result of this, eating lots of food could mean extra acid. The raised acid level, together with the additional volume, increases the possibility of heartburn - should acid escape through the oesophageal muscle.
  • Eating a big meal means there is more to digest and the digestion process takes longer. Acid levels are therefore likely to be higher for longer and again may ultimately increase the potential for heartburn.

What happens when you eat too little?

If you've decided that eating almost nothing may help you reduce or stop heartburn, you may need to rethink. Your body needs a balanced diet of various essential nutrients and the right amount of calories. If your body doesn't get them, you could end up with other health-related problems.2

Moderation can often be key to a healthy diet

Perhaps one action you should consider is to examine when you get heartburn and which foods you have eaten before getting it. Try to address those things that can trigger heartburn:

  • Cut out or down on fatty foods, such as burgers or sausages
  • Cut out spicy foods to see if this makes a difference
  • Eat smaller quantities more often, rather than 3 large meals a day
  • Reduce your intake of caffeinated drinks.

Eating foods such as vegetables, salads, lean meat (like chicken), fish, pulses, nuts and pasta can help provide you with a good dietary balance and the essential nutrients your body needs.

Treating symptoms while you are adjusting your diet

While you're trying to find a diet to suit you, you may continue to experience some heartburn. If so, Gaviscon Double Action is here to help you. And it is available over-the counter. Gaviscon Double Action forms a physical barrier on top of the stomach contents, which helps to stop acid refluxing into the food pipe.

Gaviscon Double Action also:

  • Neutralises acid
  • Gets to work instantly
  • Offers long lasting relief - up to two times longer than antacids.

If you're in any doubt about your diet and how it might be affecting your heartburn, you could consider seeing your doctor. A nutritionist or dietician can also provide you with expert guidance on diet. Ask at your local GP's surgery, they'll be pleased to help you.


All information presented is not meant to diagnose or prescribe. Gaviscon Double Action for Heartburn & Indigestion. Always read the label. If symptoms are severe or prolonged you should consult a doctor or pharmacist.