After Stomach Cancer Surgery

After stomach cancer surgery you may notice a variety of adverse effects that can arise including weight loss and nutrition problems and dumping syndrome.

Select A Topic:

  • Weight Loss - a significant issue following surgery for stomach cancer
  • Vomiting - a problem that can sometimes occur
  • Diarrhea - a change in bowel habit is common following your operation

After Stomach Cancer Surgery
The Art Of Eating Without A Stomach
The Art Of Eating Without A Stomach

Weight Loss

The most common problem post stomach cancer surgery is weight loss.

Early satiety or feeling full quickly after food and drink means that you don’t want to eat as much even though your calorie requirements are unchanged (or even increased around the time of your surgery).

Your stomach is an important organ in the digestive process and its loss means that normal digestion isn’t achievable.

Your diet needs to change to compensate for this and the use of nutritional supplements may be helpful to you.

Iron, Calcium and Vitamin B12 Deficiency

Your stomach is involved in the absorption of Iron and vitamin B12.

Iron is converted by the acid from Iron III to Iron II and it is this change that allows Iron absorption in your small bowel.

After stomach cancer surgery this can't happen so you may need to have Iron supplements to compensate if this is an issue.

Also, gastrectomy increases the transit of food through the gut and this can reduce the time available for absorption.  As  a result iron can be malabsorbed.

Vitamin B12 requires a carrier molecule known as intrinsic factor for absorption to occur in the end part of your small bowel or terminal ileum.

Intrinsic factor is produced in the gastric cells, so after gastrectomy there is no way for B12 to be absorbed. It has to be replaced with injections called Hydroxycobalamin.

Both Iron and Vitamin B12 are required to manufacture your red blood cells. Loss of one or both of them can render you anemic.

Calcium is absorbed in the small bowel and malabsorption can occur as a consequence of increased gastric emptying. It can also result from the binding of calcium to fat that can be malabsorbed too.


Bile is produced to aid fat digestion and normally passes from the liver and gallbladder through the common bile duct in to your duodenum (1st part of your small bowel).

After stomach cancer surgery bile, produced by your liver, passes freely without barrier in to your esophagus.

When this happens heartburn, nausea and vomiting can occur. This is particularly evident after sleep when you have been lying flat as gravity has no way of preventing it.

Sleeping propped up in bed may help as well as the use of prokinetic drugs which prevent reflux of bile. Examples of these include Metoclopramide and Domperidone.

Dumping Syndrome and Diet After Stomach Cancer Surgery

Dumping syndrome is an odd condition that occurs after stomach cancer surgery.

There are two forms that can occur when you have a meal.

The first is known as early dumping syndrome which normally occurs within a short time of eating (often within the first 20 minutes).

This form is caused by rapid movement of food in to your small bowel. When this happens, fluid is pulled in to the small bowel by a process known as osmosis.

When this happens, your blood pressure can drop making you feel feint, shaky and even give you sweats and palpitations.

The second is known as late dumping syndrome and is caused by carbohydrates or complex sugars you eat passing rapidly in to the small bowel.

This results in increased insulin production which in turn promotes uptake of sugar.

Because insulin levels are so high, your blood sugar level drops quickly and this can make you feel shaky and unwell, well that's the theory anyway.

Preventing Dumping Syndrome

Whether your problem is due to early or late dumping syndrome, it is important to know what to eat. You can help prevent symptoms by eating meals more slowly and be taking smaller meals more often than the usual three times a day most people are used to.

You also need to follow a post gastrectomy diet, taking carbohydrates in your meals including rice, potatoes, pasta and noodles can be helpful along with protein containing foods such as poultry, fish and eggs.

If you have symptoms within 20 minutes of a meal, having some sugar can help to resolve your symptoms.

My book, "The Art of Eating Without A Stomach" is a comprehensive guide on the best way to manage your diet.

Removing drugs that can increase the risk of dumping syndrome may also help. Examples of these include the prokinetic drugs Metoclopramide and Domperidone which stimulate food transit.

Somatostatin analogues may be considered including the drugs Lanreotide and Octreotide which can help to reduce symptoms


Diarrhea is not an uncommon problem after stomach cancer surgery. There are many reasons for this including increased transit of food through the bowel, small intestinal bacterial overgrowth or SIBO, malabsorption issues, osmotic diarrhea from dumping syndrome, drugs and the surgery itself.

Often it can be self-limiting, but the use of drugs that slow up the bowel including Loperamide and Codeine Phosphate may help.

If due to SIBO, antibiotics in pulses are given to change the bacterial flora in your small bowel and promote the growth of productive bacteria.

Somatostatin analogues already mentioned for dumping syndrome may also help in some cases.

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