Even good foods can cause some problems

Even good foods can cause havoc in your life. Here are a few to keep your eye on if you are taking medicine or have certain health problems..
•Grapefruit
Problem: Prescription drug interaction and potential kidney failure.
What happens: While grapefruit is an excellent source of vitamin C and contains fiber, potassium and lycopene for cancer prevention, it could be off-limits for those on some prescription medicines. "It can alter the effects of the drug, causing serious side effects. The biggest concerns are with cholesterol-lowering medicines. The grapefruit may prevent the liver from breaking down the drug, causing toxic levels to build up that could cause kidney failure,” said Lona Sandon, M.Ed., R.D., a professor of nutrition at the University of Texas Southwestern Medical Center at Dallas.
How much do you have to eat? "One glass of grapefruit juice or one grapefruit is enough to interfere with medications. I am not sure at what level kidney failure might occur, but it's probably not a good idea to push it. It likely depends on a person's body weight. No level of grapefruit intake is considered acceptable with these medications,” Sandon said.
•Broccoli
Problem: Prescription drug interaction and hyperoxaluria.
What happens: "Broccoli may interfere with your blood-thinning medications, putting you at greater risk for stroke,” Sandon said. This is why it is important to read the fine print about side effects on any medicines you're taking and pay attention to warnings. Additionally, too much broccoli can cause hyperoxaluria, said Maurice A. Ramirez, D.O., an emergency-room physician and author of the soon-to-be-released book "You Can Survive Anything, Anywhere, Every Time.” "This is increased urinary excretion of oxalate caused by excessive intake of oxalate-containing foods (broccoli, cauliflower, cabbage, brussels sprouts, etc.) resulting in kidney stones,” Ramirez said.
How much do you have to eat? Hyperoxaluria will occur in anyone eating more than 1 to 2 cups of broccoli who has a predisposition to calcium oxalate kidney stones. For these people, even small elevations of urine oxalate will result in the formation of crystals in the urine. If enough crystals form, you'll get stones. This is not unlike gout patients getting gout attacks (or kidney stones) from foods high in uric acid (fermented foods including beer, wine, alcohol, yeast bread, cheese, organ meats, shellfish, etc.).
•High-grit foods and/or grains (such as the whole cracked-grain pieces common in organic bread or coarsely ground, stone-ground whole grains, especially if they contain stone powder or sand) and acidic foods (such as carbonated drinks, uncooked vinegar, uncooked tomato, citrus — especially lemon — and ceviche).
Problem: Odontolysis.
What happens: Odontolysis is the degeneration or wearing down of teeth by excessive chewing of high-grit foods and/or grains or excessive use of acidic liquids.
How much do you have to eat? "For acidic foods, concentration and time of contact are what matters. For instance, drinking lemon juice is a relatively short exposure, but sucking a lemon for the same total intake is a much longer and damaging exposure. In acidic odontolysis, the process dissolves the enamel and dentin of the teeth. For grits and grains, the process is simple wear, like filing down your teeth, only slower. Unfortunately, odontolysis is not reversible, and it predisposes one to cavities and broken teeth,” Ramirez said.
•Vegetables with seeds, such as cucumbers and tomatoes.
Problem: Can exacerbate symptoms of diverticulitis.
What happens: Diverticular disease occurs when small pouches form in the colon, where nuts and seeds can get stuck. The disease is often caused by a diet with too little fiber and too little water. Although the best way to avoid the disease is to make certain you have ample dietary fiber (soluble and insoluble), if you do develop diverticulosis (which can lead to diverticulitis), you may be well-advised to initially follow a low-fiber diet, avoiding seeded fruits, vegetables and most nuts and seeds, and gradually ramp up to a high-fiber diet that promotes soft, bulky stools that pass more swiftly, said Jackie Keller, founder of NutriFit and author of "Body After Baby: A Simple, Healthy Plan to Lose Your Baby Weight Fast” (Avery/Penguin, 2006).
How much do you have to eat? "As little as a cup or two of the wrong thing can cause gas, bloating and great intestinal discomfort,” Keller said.
•Tomatoes, potatoes, peppers and eggplant.
Problem: Increased arthritis pain.