Your parent is eating less. Here is when it is normal and when to call the doctor.

A loss of more than 5 percent of body weight over 6 to 12 months, without trying, is the number doctors act on. Most families miss it, because nobody weighs their parent. They just notice the plate coming back half full.

Smaller appetites are common as people get older, and a few skipped meals do not mean anything is wrong. The hard part is telling a slow drift from a real problem when you see your parent every day and the change is gradual. A scale and a notebook settle that question better than your memory can.

This article is general information for caregivers, not medical advice. Your parent's doctor decides what is going on. Your job is to bring the doctor good notes.

The number to track

Doctors define significant unintentional weight loss as more than a 5 percent drop in body weight within 6 to 12 months (American Academy of Family Physicians). For a parent who weighs 150 pounds, that is 7.5 pounds. For 180 pounds, it is 9.

Unplanned weight loss at that level shows up in roughly 15 to 20 percent of older adults, and the causes range from a poorly fitting set of dentures to medication effects to conditions that need a real workup. Nobody can sort that out from the kitchen table. That is what the appointment is for.

Why a parent stops eating

It is rarely about the food. The Alzheimer's Association lists these common reasons for someone with dementia, and most of them apply to anyone older:

• Dentures that hurt. Eating can be painful, and your parent may not be able to tell you that. Check the fit and see the dentist.
• A new medication or a dose change. Some medications affect appetite. If the eating changed after a prescription changed, tell the doctor or pharmacist.
• Food that tastes or smells different. Reduced smell and taste make favorite meals less appealing.
• Too many choices. A full plate or a long menu can overwhelm someone with memory trouble.
• Forgetting. Your parent may forget to eat, or believe a meal already happened.
• Not moving. Less physical activity means less appetite.
• Trouble swallowing. Swallowing problems can lead to choking and weight loss, and they need a doctor's attention.

What to try at the table

None of these are cures. They remove common obstacles, and they cost little or nothing.

1. Serve one or two items at a time. A plate with fewer things on it is easier to start.
2. Use plain, solid-colored plates that contrast with the table or placemat, so the food is easy to see.
3. Switch to several small meals instead of three big ones. Offer favorite foods first.
4. Offer small cups of liquid through the day, plus foods with a lot of water in them like soup, fruit, and smoothies.
5. Make it quiet. Turn off the TV, clear the table, and sit down and eat with your parent when you can.
6. Give it time. Plan on an hour or more for a meal.
7. Make it easier to handle. Finger foods, bowls with rims, large-handled spoons, and cups with lids help someone who is losing the coordination for a fork.
8. Check the temperature before you serve, and keep your parent sitting upright while eating.

When to call the doctor

Do not wait for the 5 percent number if any of these show up:

• The eating changed soon after a new medication or a dose change.
• Coughing or choking at meals, or wet-sounding speech after swallowing.
• Your parent winces or avoids food that needs chewing.
• Your weight log shows a drop of 5 percent or more, or clothes that suddenly hang loose.
• Your parent is drinking much less than usual.

If your parent is choking and cannot breathe or speak, call 911 right away. That is an emergency, not an appointment.

What to bring to the appointment

Doctors have about fifteen minutes. A page of notes beats a general feeling that things are different.

• The weight log, with dates.
• A list of every medication and supplement, including when each one started or changed.
• Three to five days of notes: what was eaten, what was left, how much was drunk.
• Anything you noticed at meals: pain, coughing, refusing certain foods, forgetting.
• Your question, written down. For example: "What could be causing the weight loss, and what do you want to check first?"

If your parent is the one who minimizes everything, here is how to handle a parent who will not accept help.

If you are doing this alone

Meal after meal of coaxing is wearing. If you are the only one doing it, that is a sign you need backup, not a sign you are doing it wrong. The early signs of caregiver burnout are worth reading.

Help with paying for it exists too. Medicare's GUIDE Model pays up to $2,500 a year for dementia respite when your parent is enrolled with a participating provider (how it works). For anyone else, call the Eldercare Locator at 1-800-677-1116 and ask for the Area Agency on Aging that covers your parent's zip code. Ask what they offer for meals and caregiver support.

The short version

You are not looking for one dramatic meal. You are looking for a slow trend, and the only way to see it is to write it down.