After gastric cancer surgery, the body gradually settles. Your meal portions increase little by little, and your weight stops at a certain line. Yet quite a few people find that at some point a year or two after surgery, their energy suddenly drains away and they get short of breath even just climbing stairs. When tested, it is often anemia, or vitamin B12 hitting bottom. In fact, this is not a failure to recover well, but a change that slowly emerges in the place where the organ called the stomach is now missing.
The stomach is not simply a pouch that holds food. The stomach acid that comes from the stomach wall changes the iron in food into a form the body can easily absorb, and it also makes a protein called 'intrinsic factor' that helps vitamin B12 be absorbed in the intestine. So when the stomach is removed in part or in whole, these two routes weaken or are cut off. Iron deficiency usually shows up as anemia within a few months to a year after surgery, while because our body has a reserve of B12 for several years, it only depletes much later and produces symptoms. So the problem flares up at the very point when you think "I've fully recovered now, why is this happening."
The vague nature of the symptoms is another headache. They are easy to brush off as just age or fatigue. When iron is lacking, the face turns pale, you tire easily, and nails may break easily. When B12 becomes deficient, on top of this, neurological symptoms creep in — the tongue burns, the hands and feet tingle, and sensation dulls. Since this nerve-side damage tends to recover slowly if left for a long time, rather than vaguely enduring, checking once with a blood test puts your mind at ease.
Management is simpler than you think. Get iron from foods like lean meat, liver, egg yolk, and spinach, and absorption improves if you add vegetables or fruit rich in vitamin C. Conversely, strong coffee or tea right after a meal hinders iron absorption, so it is better to leave a little gap. However, those who have had stomach surgery often cannot keep up with food alone, so the shortfall is supplemented with iron pills. Oral B12 supplements may not work well, so many people use the method of receiving injections periodically. It is not one and done — it is common to continue at intervals of a few months while watching the body's condition.
Above all, the key is regular blood tests. If you catch it by the numbers before symptoms appear, you can get through it that much more lightly. After surgery, items such as hemoglobin, ferritin (iron storage), and vitamin B12 are usually checked together on a set schedule. If you see these items on your test result sheet, do not just pass them by — track the trend. If you see a downward flow, you can take action early.
This piece is only general information, so the supplement dose and injection interval differ from person to person. Be sure to decide your own numbers and symptoms in consultation with your attending medical staff.