The end of the year is fast approaching, and with it comes an end to many holiday indulgences. Overeating and related weight gain spur many people to resolve to improve their diets and increase their activity level with the new year.

Making those changes is often easier said than done if the healthier foods seem to cause physical distress.

But you are not alone. It is estimated that 10 percent to 15 percent of people in the U.S. report regular difficulties with stomach pain, bloating, gas, diarrhea or constipation related to the types of food they’ve eaten.

many of these people have been diagnosed with irritable bowel syndrome (IBS). IBS sufferers often report difficulties with one or more different foods. sometimes, though, they just aren’t sure what is causing their distress.

Taking a hard look at a person’s daily food intake, along with any symptoms suffered can start to decode what food items may be the most at fault. this involves carefully looking at all ingredients on food labels, as well as keeping a food and symptom record listing all foods eaten daily and any gastrointestinal (GI) side effects.

If problem foods are unknown, a good starting point should be a close look at your food record for the four most common food intolerances: Milk, soy, fructose and gluten.

Milk

Intolerance most commonly involves milk sugar and lactose. Lactose intolerance affects 15 percent of the general population. In certain ethnic groups, such as Native Americans and Asians, the rate is even higher.

It can also develop as we age when our bodies produce less lactase, which is the enzyme needed to digest lactose. It might also be a side effect of other GI issues, such as Crohn’s or gluten intolerance.

Avoid: Milk, yogurt, cream, curds, ghee, ice cream, butter, buttermilk, cheeses, nougat, rennet, whey, casein and milk solids.

Soy

A person doesn’t have to eat tofu or drink soymilk to have soy in their diet. Soy is used in many foods in the U.S. Soy oil use is widespread by food manufacturers, and it is also used as a meat extender.

Avoid: Soy (all forms), hydrolyzed soy protein, miso, natto, shoyu sauce, soya, tamari, tempeh, tofu, textured vegetable protein (TVP), edamame and soy sauce.

Fructose

Fructose intolerance involves a sensitivity to the sugar found in fruit. this is especially true for foods that have a higher fructose content than glucose content.

Avoid: Fructose, high-fructose corn syrup, fruit juices, large portions of fruit. some fruits such as apricots, apples, pears, cherries, watermelon and dried fruits may be especially bothersome because of their higher fructose content.

Gluten

those with a gluten intolerance need to avoid the protein found in wheat, barley and rye.

Wheat is widespread in the U.S. food supply, which makes this task quite tricky.

Eating foods in their most-natural, least-processed form helps to make following a gluten-free diet easier.

those with a gluten intolerance should also avoid sauces, gravies, salad dressings and other condiments unless labeled gluten-free.

Avoid: Wheat, barley, rye, bran, bulgur, couscous, durum, farina, flour, gluten, kamut, matzo, seitan, semolina, malt, malt flavoring, malt vinegar, spelt, triticale, graham flour, soy sauce, chicken broth, brown rice syrup and bouillon.

A food log will allow you to better determine whether GI issues are because of one or more of these common food intolerances. the log will allow you to look at when you developed symptoms and what you ate in the previous 24 to 72 hours. If some of the same food groups keep showing up before you have symptoms, you have likely identified a problem food.

the stronger the intolerance, the sooner the connection with a problem food can be identified.

once identified, try eliminating a problem food from the diet for two weeks to see if symptoms disappear.

If they do, challenge yourself by eating some of the problem food to see if symptoms reoccur. If they do pop up again, you have successfully identified an intolerance to that food.

Learning what foods cause you distress gives you freedom to enjoy all the rest.

Note: Severe reactions to foods such as throat and lip swelling, difficulty breathing, hives or rashes are not intolerances but are symptoms of food allergy and require immediate medical attention and continued avoidance of that food item.

Cathie Brookhart is a clinical/outpatient dietitian Gettysburg Hospital. Healthy Helpings is a column written by nutritionists in York and Adams counties.