Diet After Gastric Bypass:
3 MUST Knows

diet after gastric bypass

Your stomach is reduced from the size of a football to approximately the size of an egg after gastric bypass surgery.

Also called “Roux-en-Y” (RNY) or “bypass” for short…

…the gastric bypass helps you lose weight because it vastly reduces the size of your stomach. AND it ALSO makes you malabsorb calories.

This means you eat smaller amounts of food, PLUS you won’t absorb all the calories from that smaller amount of food! If you drink a protein shake with 160 calories, you won’t absorb all 160 calories. That’s what “malabsorbing” means.

Gastric bypass (RNY) surgery is therefore a “restrictive” AND “malabsorptive” surgery, whereas the gastric sleeve (VSG) and adjustable gastric band (AGB) are simply “restrictive” surgeries.

That being said, the malabsorption after gastric bypass raises a nutrition concern:

cartoon football
hard boiled egg

Diet After Gastric Bypass:
1. Possible Nutrient Deficiencies

While malabsorbing calories may sound like a dream come true…

…it’s a double-edged sword. It also means you don’t absorb all the vitamins and minerals in your food, and this can lead to deficiencies down the road if you don’t supplement properly.

A majority of the stomach and a portion of the intestine are both bypassed or “skipped over” with the RNY. The part of the intestine that gets bypassed is responsible for absorbing calories as well as 5 important vitamins and minerals:

  • Vit A
  • Vit D
  • B12
  • Iron
  • Calcium

This means you’re at risk of getting deficient in these nutrients if you don’t take dietary supplements. Bariatric specific vitamins are the best choice because they're formulated specifically with what you need.

Diet After Gastric Bypass:
2. You Won't Feel Hungry

The hormones responsible for hunger are produced in the part of the stomach that's bypassed. That means you won't feel physically hungry...

...for awhile anyway. (Some patients report a return in hunger after many months or years following surgery.)

While it may sound dreamy to not feel hungry, it can be a barrier to meeting your protein goal. It's helpful to set up a schedule and eat at regular planned times every 3-4 hours in the early post op months in order to avoid skipping meals and under eating. Your body's lack of hunger cues won't be a good guide. Undereating is just as extreme as overeating! How often you should eat will change over time.

Diet After Gastric Bypass:
3. No Guarantee

A smaller stomach (“pouch”) holds less food. This results in eating less calories. Plus, you don’t absorb all the calories you eat. Plus you don't feel hungry, so sticking with small portions is natural. Collectively, this results in weight loss. That's how the diet after gastric bypass works.

However...there’s no money back guarantee.  Just as owning a watch doesn’t guarantee you’ll always be on time, having gastric bypass surgery doesn’t guarantee weight loss. You must do your part. The goal after surgery isn't to eat smaller portions of the foods that got you to surgery in the first place. The goal is to totally overhaul your diet. You MUST do your part or you will regain your weight.

I like to think of weight loss surgery as a 3 legged stool. If any one of the legs buckles, the whole stool comes tumbling down:

  1. Gastric bypass surgery
  2. YOU: your commitment to choosing the right foods
  3. Follow up/accountability

Following the gastric bypass diet is like training for a long race. A long, long, long race. Not a sprint.

It may feel uncomfortable in the beginning when everything is new, but once you get through the learning curve, it will get easier. And if you're in need of a little extra help, you can work with me virtually.

In Order to FULLY Understand the Gastric Bypass Diet, You MUST Know About Each of the "5 R's:" 

The “5 R’s” of the Bariatric Diet describe how the whole journey looks from the time you start to prepare for weight loss surgery thru all the years beyond:

Getting Ready for Surgery

The Recovery

Rapid Weight Loss

Rest of Your Life

Potential Regain

You might like these