People with chronic kidney disease know how it can turn a life upside down.

But by making some simple diet changes, sufferers can help their bodies cope and even delay the progression of the disease.

As with most serious medical conditions, some foods can't be eaten at all.

But even with kidney disease, people can still have a lot of their favorites if they stick to three rules:

1. Eat fresh
2. Eat frequently
3. Control portion size

Most people develop a regular route around the grocery store.

But for those newly-diagnosed with chronic kidney disease, or CKD, dietitian Susie Beckett said it's time to steer in a new direction.

"The kidney diet is one of the most difficult diets out there to do because it has multiple dietary factors you have to consider," Beckett said.

Many CKD patients already have high blood pressure and diabetes, so Beckett said a diet rich in proteins, low-fat dairy and fresh fruits and vegetables is a must.

But even fruit requires proper portions.

"You want to think about something between the size of a golf ball and tennis ball is a good size for a fresh fruit," Beckett said.

Whole-grain breads are a healthy choice if you're in the low stages of kidney disease.

"It's going to help with their blood pressure and diabetes, but they may be higher in phosphorus and potassium, which may need to be eliminated in the higher stages of CKD," Beckett said.

Potassium, phosphorous and sodium are dangerous for CKD sufferers, and Beckett said they're all hidden in the deli section.

"The deli can be a mine field for lots of sodium and phosphorous for our people," Beckett said.

But fresh, lean meats and fish are encouraged, in moderation of course.

"A deck of cards is about three ounces. So our average female would need about two decks of protein a day," Beckett said.

In the dairy section, Beckett said people with CKD should choose low-fat yogurt, cheese and milk or even a soy product.

"If your stages of kidney disease increase, you're going to want to find some alternatives for milk," Beckett said.

But Beckett said the biggest thing to get rid of with kidney disease is extra salt.

Add as many herbs as you want, eat smaller meals more often and be willing to try new things.

Another big theme of the kidney diet is avoiding processed foods.

Eat fresh foods as much as you can, but before you make any big changes to your diet, check with your doctor first.

Dietitian Gives Kidney-Healthy Menu Tips