When people spend time in the hospital, especially in intensive care units, their muscles can shrink quickly—losing up to 15% of muscle mass each week. Researchers studied 120 hospital patients to see how different types of nutrition support could slow this muscle loss. They found that patients who received nutrition through their digestive system (rather than through an IV) kept more muscle mass. Adding extra protein also helped patients maintain their grip strength. While early nutrition support couldn’t completely stop muscle loss, it made a real difference in helping patients stay stronger during their hospital stay.
The Quick Take
- What they studied: How quickly hospital patients lose muscle during their stay, and whether different types of nutrition support can help prevent this muscle loss.
- Who participated: 120 adults (18 years and older) admitted to either regular hospital wards or intensive care units who needed at least one week of special nutrition support. About one-third were in regular wards, and two-thirds were in ICU.
- Key finding: Patients who received nutrition through their digestive system (tube feeding) lost less muscle than those who received nutrition through an IV. Patients getting extra protein also maintained better grip strength. However, all hospital patients still experienced some muscle loss, especially those in intensive care.
- What it means for you: If you or a loved one faces a hospital stay requiring nutrition support, tube feeding appears to be better for muscle preservation than IV nutrition. Extra protein may help maintain strength. However, this study shows that muscle loss during hospitalization is common and difficult to completely prevent, even with good nutrition support.
The Research Details
This was an observational cohort study, which means researchers followed a group of patients over time and measured what happened to them, rather than randomly assigning them to different treatments. Researchers enrolled 120 adults admitted to hospitals who needed at least 7 days of nutrition support through either tube feeding (enteral nutrition) or IV nutrition (total parenteral nutrition). They measured muscle mass using two methods: a bioelectrical impedance test (which sends a harmless electrical signal through the body to estimate muscle) and ultrasound imaging. They also tested grip strength, weight, and a measurement called “phase angle” that shows how well cells are hydrated and functioning. All measurements were taken when patients started nutrition support and again after 7 days.
This research approach is important because it shows what actually happens to real patients in hospital settings, rather than just what happens in controlled laboratory conditions. By comparing different nutrition methods and protein supplements in the same study, researchers could identify which approaches work best for preserving muscle. The study also looked at patients with different levels of malnutrition, which helps doctors tailor nutrition plans to individual needs.
This study has several strengths: it measured muscle using two different methods (bioelectrical impedance and ultrasound), it included both regular ward and ICU patients, and it adjusted results for other factors that might affect outcomes. However, the study only followed patients for 7 days, which is a short time period. The study was observational rather than randomized, meaning patients weren’t randomly assigned to different nutrition types—they received what their doctors thought was best. This means some differences between groups might be due to how sick patients were rather than the nutrition type itself. The sample size of 120 is moderate, which limits how confident we can be about some findings.
What the Results Show
ICU patients experienced significant muscle loss over the 7-day study period. Their weight dropped by 4.4%, their BMI (body mass index) decreased by 1.2%, and their muscle thickness decreased by 6.9%. All patients—both in ICU and regular wards—experienced notable loss of grip strength, with declines ranging from 5-10 kilograms on average, and some patients losing up to 39.8% of their grip strength. This shows that muscle loss during hospitalization affects both the size of muscles and how strong they are. The type of nutrition support made a meaningful difference: patients receiving tube feeding (enteral nutrition) gained about 2% in weight, while those receiving IV nutrition (TPN) lost 2% of their weight. When researchers adjusted for other factors, tube feeding was associated with 5.2% better muscle preservation compared to IV nutrition.
Extra protein supplementation (specifically a 30-gram leucine-enriched protein module) showed protective effects on grip strength, with patients receiving it maintaining about 24% better grip strength compared to those without supplementation. Patients with moderate malnutrition (based on a nutritional assessment called SGA-B) lost about 2.8% of their weight, while severely malnourished patients (SGA-C) actually stabilized their weight, suggesting that nutrition support was particularly helpful for the most malnourished patients. In regular ward patients, a measurement called phase angle increased by 10.8%, which suggests their cells were becoming better hydrated and functioning better—a sign of recovery.
Previous research has shown that hospitalized patients can lose up to 15% of muscle mass per week, and this study confirms that muscle loss is a serious problem during hospital stays. The finding that tube feeding preserves more muscle than IV nutrition aligns with other research suggesting that using the digestive system when possible is beneficial. The protective effect of extra protein is consistent with nutritional science showing that protein is essential for maintaining muscle. This study adds to existing knowledge by showing these effects specifically in hospitalized patients receiving early nutrition support.
The study only lasted 7 days, so we don’t know what happens to muscle over longer hospital stays. The study was observational, meaning doctors chose which type of nutrition each patient received based on their medical condition, so sicker patients might have been more likely to receive IV nutrition. This makes it harder to know if differences between groups are due to the nutrition type or the patients’ underlying conditions. The study didn’t randomly assign patients to different nutrition types, which would provide stronger evidence. The sample size of 120 is moderate, so some findings (especially in subgroups) should be interpreted cautiously. The study didn’t follow patients after they left the hospital, so we don’t know about long-term recovery.
The Bottom Line
Based on this research, when hospitalization requiring nutrition support is necessary: (1) Tube feeding (enteral nutrition) appears preferable to IV nutrition for muscle preservation—confidence level: moderate; (2) Extra protein supplementation may help maintain grip strength—confidence level: moderate; (3) Early nutrition support should be started as soon as medically appropriate, as it helps slow (though doesn’t prevent) muscle loss—confidence level: moderate. These recommendations should always be discussed with your medical team, as the best nutrition approach depends on individual medical conditions.
This research is most relevant to: people facing planned hospital stays requiring nutrition support, families of ICU patients, hospital nutritionists and doctors planning nutrition care, and older adults who are at higher risk for muscle loss. People with existing muscle weakness or malnutrition should pay special attention to nutrition planning before and during hospitalization. This research is less directly applicable to people having short hospital stays (less than 7 days) or those who can eat normally during hospitalization.
Based on this study, meaningful changes in muscle preservation can be seen within 7 days of starting appropriate nutrition support. However, complete prevention of muscle loss isn’t realistic—the goal is to slow it down. Recovery of lost muscle typically takes weeks to months after leaving the hospital, depending on how much was lost and the patient’s overall health. Grip strength improvements from protein supplementation may be noticeable within days to weeks.
Want to Apply This Research?
- If hospitalized, track weekly measurements of grip strength (using a simple grip strength test available at most hospitals or rehabilitation centers) and body weight. Record these weekly to monitor muscle preservation progress. Also note the type of nutrition support received (tube feeding vs. IV) and any protein supplements added to meals.
- Before hospitalization: work with your doctor to plan nutrition support in advance, ensuring tube feeding is used if possible and discussing protein supplementation needs. During hospitalization: advocate for early nutrition support, ask about protein-enriched options, and request grip strength testing to monitor muscle preservation. After hospitalization: prioritize protein intake and physical rehabilitation to rebuild lost muscle.
- Track grip strength monthly for 3 months after hospital discharge as a marker of muscle recovery. Monitor body weight weekly during recovery. Work with a physical therapist or rehabilitation specialist to assess muscle function through simple tests like walking speed or stair climbing ability. Report significant declines in strength or function to your doctor.
This research describes what happened in one study of 120 patients over 7 days and should not replace personalized medical advice. Nutrition support decisions during hospitalization must be made by your medical team based on your specific health conditions, medications, and medical history. If you are facing hospitalization or have concerns about muscle loss, discuss nutrition planning with your doctor or a registered dietitian. This information is educational and not a substitute for professional medical guidance.
This research translation is published by Gram Research, the science division of Gram, an AI-powered nutrition tracking app.