Is it true that I can’t eat corn on the cobb or even bite into a hamburger/sandwich with veneers?

Dental veneers are designed to handle normal biting and chewing, but there are still a few foods you should avoid, particularly when wearing temporary veneers. 
Foods to avoid if you have temporary veneers
During the first step of the veneer process, your dentist files the fronts of your teeth and takes molds of them. The dental laboratory uses these molds along with the dentists notes to create your custom veneers, which should be ready in about two to three weeks. In the meantime, you'll probably wear temporary veneers. Since these veneers aren't permanently attached to your teeth, they can move or become damaged if you aren't careful. Avoiding the following foods can help you prevent problems:
Meat that requires substantial chewing, such as steakIce, hard candy, apples and other hard foodsToast and breads with hard crustsSticky candiesNut, potato chips, pretzels, seeds and other crunchy foodsFoods that can stain teeth, such as coffee, tea, wine, cola, ketchup, tomatoes and berriesOnce you receive your permanent veneers, you may want to avoid or limit these types of foods and actions:
Hard Foods: It's never a  good idea to bite into hard candies or biting close to the bone when eating foods like pork chops and chicken legs.  Things like these can chip the porcelain..Ice: Biting down on ice cubes can chip or break your veneers.Using teeth like a tool:  biting open a bag of chips.  Avoid biting your nails or anything with exessive vertical force. Otherwise treat your veneers as you would your natural teeth.

Hi Wookie from  Maryland!  You need to be cautious!  Temporary veneers are not as strong as the permanent ones.  When you have your permanent ones in you need to take extra care of them for awhile.  They are as good as the dentist who put them in and the lab that made them and how well you take care of them. No crunching ice or opening bottles with them!

It is always good to exercise caution.  Ultimately we as dentists want what's best for our patients and our restorations to last, but at the same time we have to face the reality that patients want to go about their daily lives, and continue to eat foods they enjoy having.  We can only give suggestions and mention worst case scenarios so that you are aware.  However with modern dentistry, material strength and bonding technique has been greatly enhanced without compromising esthetics so there is less concern about porcelain chipping or cracking than years ago.  Durability and longevity also depend on the clinician's skill, technique, and expertise.  Porcelain veneers can also potentially "de-bond" and pop out if preparation is not planned and executed carefully.  Although I would not suggest biting into your nails, pens, pencils and chewing hard foods like meat close to the bone, extremely hard breads or ice, you can generally get away with eating the foods you like.  Just be mindful of what you are eating and use your best judgement.  Try to get into the habit of cutting harder foods into smaller pieces and chewing with your back teeth.  I would also recommend wearing a custom-made nightguard for added protection.  But if it's corn on the cub or a hamburger (bun not too hard) you crave, enjoy!  I hope this helps!