Dear FS: You can have too much of any food, and fiber is no exception. While there are proven health benefits to having the recommended intake level, it’s best to avoid an unusually high amount of fiber each session. This is especially true if one is working towards the recommended standard, as you are.

The human body is programmed to use its resources and energy efficiently. This natural preference for digestive economy results in physical adaptations to any habitual eating style. In other words, our body gets used to the way we normally eat.Most people have had different reactions when trying new seasonings or cuisines. Traveling to a remote location and adjusting your meal schedule to local time would have a similar effect. Either way, your body might find ways to tell you, “I wasn’t quite prepared for this.

As for fiber, it provides unabsorbed bulk that affects the speed at which food moves through the digestive tract. So it also affects what ends up in the large intestine to be worked on by our microbiome.(See some frequently asked questions about the microbiome at b.link/2446rv.) Adding large amounts of fiber to a system that’s not used to it can lead to short-term bouts of cramping, bloating, diarrhea, and gas, which isn’t ideal in social situations. All of this can be made worse, and even become risky, if large amounts of fiber are consumed without enough fluid.

Assuming there are no issues with your digestive system, there is no reason to avoid fiber for its transient side effects. A sensible strategy is to slowly but steadily incorporate high-fiber foods into your daily routine until you reach the recommended level of about 25-30 grams per day. Learn more about dietary fiber at b.link/j43qu.

Dear Dr. Blonz: I cleaned out a kitchen cabinet and had to make decisions about my stored cereal. What is the shelf life of flours and other cereals? In particular, I’m interested in the polenta: it seemed fine in its sealed bag, but had been there for about a year. — KLB, Dobbs Ferry, New York

Dear KLB: Grains, especially whole grains, should be stored in a cool, dry place in airtight containers. Whole grains contain the germ and endosperm, with the components necessary to start and nurture the next generation of the plant until it can open its shoot and begin to harvest energy from the sun. The sprout also contains essential fatty acids and other essential nutrients for this purpose. The bran is the outer covering that protects the grain from oxidation and other physical or microbiological attacks that could harm new growth.

Although each grain has its unique properties, over time these protections wear off, giving edible grains their “shelf life”. Whole grains will keep for four to six months on the shelf and longer in the freezer. See Oldways Whole Grains Council information and storage chart at b.link/etw5st.

If your polenta is in its original sealed bag, it should be labeled with a freshness date, but it looks like it’s way past that.

Ed Blonz, Ph.D., is a nutritional scientist and assistant clinical professor at the University of California, San Francisco. He is the author of “The Wellness Supermarket Buying Guide” e-book (2012), which is also available as a free digital resource at blonz.com/guide.