Doctors need to know exactly how many calories cancer patients should eat to help them stay healthy during treatment. This study looked at 11 different research projects involving 439 people with head and neck cancer to see how much energy their bodies actually use. Researchers found that the standard formulas doctors use to estimate calorie needs are pretty close to accurate for groups of patients, but they might not be perfect for individual people. The study suggests that doctors should use more precise measurement tools when possible to make sure each patient gets exactly the right amount of nutrition during their cancer treatment.

The Quick Take

  • What they studied: How many calories the bodies of people with head and neck cancer actually burn, and whether the standard formulas doctors use to calculate calorie needs are accurate
  • Who participated: 439 adults with head and neck cancer at various stages of their disease, gathered from 11 different research studies
  • Key finding: The standard formulas doctors use to estimate calorie needs were slightly higher than what patients actually needed (off by about 110 calories per day), but this small difference probably doesn’t matter much in real life. Energy needs stayed fairly stable during treatment and dropped a little bit after treatment ended.
  • What it means for you: If you have head and neck cancer, the calorie estimates your doctor gives you are likely reasonable for helping you stay nourished. However, doctors should ideally use more precise measurement methods for individual patients to ensure the most accurate nutrition plans. Talk to your healthcare team about your specific nutrition needs.

The Research Details

This was a systematic review and meta-analysis, which means researchers looked at 11 existing studies about energy use in head and neck cancer patients and combined their results. They searched four major medical databases to find all relevant studies published up to May 2024. The researchers only included studies that measured actual energy expenditure using scientific methods (indirect calorimetry, which measures how much oxygen your body uses as a sign of calorie burning). They looked at how measured energy compared to predicted energy from standard formulas, and how energy changed before and after cancer treatment.

The researchers were very careful about study quality, using a system called GRADE to rate how confident they could be in the findings. They looked at whether studies compared cancer patients to healthy people without cancer, whether they tested predictive equations, and whether they measured the same patients multiple times during treatment.

Accurate calorie estimates are really important for cancer patients because proper nutrition helps them maintain strength, heal better, and handle treatment side effects. If doctors overestimate or underestimate calorie needs, patients might not get the right nutrition support. This review helps doctors understand whether the quick calculation methods they typically use are good enough or if they need to use more precise measurement tools.

The certainty of evidence was rated as ’low’ for most findings, which means there’s room for improvement in future research. All studies measured resting energy (calories burned at rest), but none measured total daily energy use or tested wearable fitness trackers. The studies included relatively small numbers of patients, and there was some variation in how they measured and reported results. However, the fact that multiple studies showed similar patterns increases confidence in the overall findings.

What the Results Show

The average resting energy expenditure for head and neck cancer patients before treatment was about 1,502 calories per day. When researchers compared what patients actually burned to what standard prediction formulas estimated, they found the formulas predicted about 110 calories less per day than what patients actually needed—a difference of roughly 7% of total calories. While this sounds like a meaningful difference, the researchers concluded it’s probably not large enough to cause real problems in patient care.

After cancer treatment, patients’ energy expenditure decreased by an average of 140 calories per day. This makes sense because treatment can affect metabolism and patients may be less active during recovery. However, this change was also relatively small compared to overall energy needs.

When researchers looked at one study that compared cancer patients directly to healthy people without cancer, they found no significant difference in how many calories each group burned at rest. This suggests that head and neck cancer itself doesn’t dramatically change the body’s basic energy needs, though treatment might.

The research showed that energy needs were relatively stable throughout the cancer treatment period, which is helpful information for planning nutrition support. The fact that all studies used the same measurement method (indirect calorimetry) made it easier to combine results, but it also means we don’t have information about whether other measurement methods or wearable devices would work well for these patients.

This is one of the first comprehensive reviews to specifically look at actual measured energy expenditure in head and neck cancer patients. Previous research in other cancer types has sometimes found bigger differences between predicted and actual energy needs, so this study suggests head and neck cancer patients might be somewhat different. The findings support the idea that standard prediction formulas work reasonably well for groups of patients, which aligns with what doctors have observed in practice.

The study only included 11 research projects with a total of 439 patients, which is a relatively small number spread across many different studies. Most studies were small, which limits how confident we can be in the results. The research only looked at resting energy expenditure, not total daily energy use (which includes activity and digestion). No studies tested wearable devices or newer measurement technologies. The studies came from different countries and used slightly different methods, which can make results harder to compare. Finally, the certainty of evidence was rated as ’low,’ meaning more research is needed to confirm these findings.

The Bottom Line

For head and neck cancer patients as a group, standard prediction formulas for estimating calorie needs appear to work reasonably well (moderate confidence). However, for individual patients, doctors should consider using more precise measurement methods like indirect calorimetry when available to ensure the most accurate nutrition planning (low confidence). Patients should work with a registered dietitian who specializes in cancer care to develop a personalized nutrition plan.

This research is most relevant for people with head and neck cancer and their healthcare teams, including doctors, nurses, and dietitians. It’s also important for cancer centers and hospitals developing nutrition support programs. People with other types of cancer should note that their energy needs might be different and shouldn’t assume these findings apply to them. Family members and caregivers involved in meal planning should also find this information helpful.

Energy needs typically stabilize within a few weeks of starting treatment. Most patients should see their nutrition plan become more stable and predictable within 4-6 weeks. After treatment ends, it may take several weeks to months for energy needs to fully adjust as the body recovers.

Want to Apply This Research?

  • Track daily calorie intake and weight weekly. Set a target based on your doctor’s recommendation (typically around 1,500 calories per day for head and neck cancer patients, adjusted for your body size). Log meals and snacks to ensure you’re meeting your calorie goal, and note any changes in appetite or energy levels.
  • Work with your healthcare team to set a realistic daily calorie target. Use the app to plan meals that meet this target, focusing on nutrient-dense foods that are easy to eat (smoothies, soups, soft foods). Set reminders for meals and snacks, especially if treatment affects your appetite. Share your tracking data with your dietitian at appointments.
  • Check your weight weekly and track it in the app. Monitor how you feel energy-wise and note any changes in appetite or ability to eat. Share weekly summaries with your healthcare team. If your weight drops more than 5 pounds in a month or you’re consistently missing your calorie goal, alert your doctor or dietitian immediately.

This research summary is for educational purposes only and should not replace professional medical advice. Energy and nutrition needs vary significantly between individuals and depend on many factors including cancer stage, treatment type, body composition, and overall health. Always work with your oncology team and a registered dietitian who specializes in cancer nutrition to develop a personalized nutrition plan. Do not change your diet or nutrition support based solely on this information without consulting your healthcare provider. If you have head and neck cancer or are undergoing cancer treatment, seek guidance from qualified medical professionals before making any dietary changes.