Story
Eating in Later Life
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In one pass Older people eat less partly because of what happens inside the body: the signals of fullness arrive earlier and louder.
Educational content, not medical advice — consult a clinician.
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Chapter 1
Why appetite shrinks with age
Older people eat less partly because of what happens inside the body: the signals of fullness arrive earlier and louder. It is not just that their taste has become fussy. This shrinking of appetite and intake is called the anorexia of aging. It is common, but it is not an unavoidable part of getting old (Landi 2016).
At least three things change. The first is slower stomach emptying: food leaves an older stomach more slowly, and the slower it leaves, the less hungry a person feels after a meal (Clarkston 1997). The second is a stronger fullness signal: when food reaches the small intestine, the gut wall releases a fullness signal called cholecystokinin (CCK), and healthy older adults have more CCK in their blood than younger adults and feel less hungry (Johnson 2020). The third is a smaller energy need: with less muscle, the body simply burns less (Volkert 2022).
The body's ability to correct itself also weakens. In a small study, men first ate less for three weeks and then ate freely. The younger men ate more on their own and regained the weight; the older men did not (Roberts 1994). So weight lost during an illness or a few weeks of poor appetite may not come back by itself in an older person.
If an older person is eating and drinking very little and suddenly becomes confused or hard to wake, call emergency services now. The chapter When an older parent needs a doctor lists every situation that needs a doctor.
At least three things change. The first is slower stomach emptying: food leaves an older stomach more slowly, and the slower it leaves, the less hungry a person feels after a meal (Clarkston 1997). The second is a stronger fullness signal: when food reaches the small intestine, the gut wall releases a fullness signal called cholecystokinin (CCK), and healthy older adults have more CCK in their blood than younger adults and feel less hungry (Johnson 2020). The third is a smaller energy need: with less muscle, the body simply burns less (Volkert 2022).
The body's ability to correct itself also weakens. In a small study, men first ate less for three weeks and then ate freely. The younger men ate more on their own and regained the weight; the older men did not (Roberts 1994). So weight lost during an illness or a few weeks of poor appetite may not come back by itself in an older person.
If an older person is eating and drinking very little and suddenly becomes confused or hard to wake, call emergency services now. The chapter When an older parent needs a doctor lists every situation that needs a doctor.
Evidence · What each of these studies measured
Stomach emptying (Clarkston 1997): 14 healthy adults aged 70 to 84 and 19 younger adults aged 23 to 50 ate the same meal. Half of the solid food left the older stomachs in about 182 minutes, against about 127 minutes in the younger group; for liquids it was about 47 minutes against about 35. After the meal the older group wanted to eat less and felt less hungry, yet did not feel clearly fuller. The more slowly solids emptied, the less hungry people felt after eating.Fullness signals (Johnson 2020): this pooled 35 studies, with 710 healthy older adults averaging 73 years old and 713 younger adults averaging 28. The older adults had higher CCK both when fasting and after meals, and higher leptin and after-meal insulin. They also ate less energy and felt less hungry when fasting. These are comparisons at one point in time: they show the signals travel together with a small appetite, but they cannot prove on their own which causes which.
Are older people more sensitive to CCK? (MacIntosh 2001): when 12 older and 12 younger adults were given CCK into a vein, it cut the older group's meal by about 32% and the younger group's by about 16%. But for the same rise in blood CCK, both groups cut their intake by the same amount. So older people are not more sensitive to it; they simply have more of it.
Weight that does not come back (Roberts 1994): 35 healthy men ate more or less than they needed for 21 days and then ate as much as they liked. The younger men ate less after overeating and more after undereating, and their weight returned to where it had been. The older men corrected in neither direction. The study included only men and was small, so it needs confirming.
macintosh-2001-cck-aging
Chapter 2
Taste and smell fade
Most of what we call the flavor of food is tasted by the nose. As we chew, aromas rise from the back of the mouth into the nasal cavity, and the brain combines them with the sour, sweet, bitter and salty signals from the tongue. With age, smell is often the first sense to fade.
In a study that gave a smell identification test to 1955 people, scores were best from the 20s to the 40s and fell clearly after 70. More than half of people aged 65 to 80 had a marked loss of smell, and more than three-quarters of those over 80 (Doty 1984). The authors note that this fits the common complaint among older people that food has no taste. Besides age, some diseases (especially Alzheimer disease) and many common medicines also dull taste and smell (Schiffman 1997).
When food cannot be tasted or smelled properly, much of the pleasure of eating goes, intake drops with it, and diets such as eating less salt become harder to keep. A review notes that giving food more flavor can help older people enjoy it more and eat a little more (Schiffman 1997). At home, that means building aroma with garlic, ginger, scallions, spices and vinegar, rather than just adding salt.
There is also a safety point: people with a poor sense of smell cannot smell a gas leak or food that has gone off (Doty 1984). A gas alarm at home, and checking the date on leftovers, are more reliable than the nose.
In a study that gave a smell identification test to 1955 people, scores were best from the 20s to the 40s and fell clearly after 70. More than half of people aged 65 to 80 had a marked loss of smell, and more than three-quarters of those over 80 (Doty 1984). The authors note that this fits the common complaint among older people that food has no taste. Besides age, some diseases (especially Alzheimer disease) and many common medicines also dull taste and smell (Schiffman 1997).
When food cannot be tasted or smelled properly, much of the pleasure of eating goes, intake drops with it, and diets such as eating less salt become harder to keep. A review notes that giving food more flavor can help older people enjoy it more and eat a little more (Schiffman 1997). At home, that means building aroma with garlic, ginger, scallions, spices and vinegar, rather than just adding salt.
There is also a safety point: people with a poor sense of smell cannot smell a gas leak or food that has gone off (Doty 1984). A gas alarm at home, and checking the date on leftovers, are more reliable than the nose.
Chapter 3
Not thirsty, yet short of water
An older person who does not feel thirsty may still be short of water. Thirst, the signal that tells us to drink, comes later and more weakly with age.
When the blood becomes more concentrated, the brain does two things at once: it makes us thirsty, and it releases antidiuretic hormone, which tells the kidneys to hold on to water. Water & Electrolytes explains this alarm. In one study, 7 healthy men aged 67 to 75 and 7 aged 20 to 31 went 24 hours without water. The older men's blood became more concentrated and their antidiuretic hormone rose higher, yet they felt less thirsty and drank less, and afterwards their blood did not dilute back to where it had been. Their kidneys also could not concentrate urine as well as the younger men's (Phillips 1984). In other words, the alarm signal is still there, but both ends, thirst and the kidneys, have loosened.
So older people should not wait to feel thirsty before drinking. The older-adult nutrition guideline of the European Society for Clinical Nutrition and Metabolism (ESPEN) recommends offering older women at least 1.6 liters and older men at least 2.0 liters of drinks a day, unless a medical condition calls for something different. People whose doctor has limited their fluids for heart failure or kidney disease should follow their doctor (Volkert 2022). Keeping a cup within reach and drinking at set times, with meals and medicines, is more reliable than waiting for thirst.
When the blood becomes more concentrated, the brain does two things at once: it makes us thirsty, and it releases antidiuretic hormone, which tells the kidneys to hold on to water. Water & Electrolytes explains this alarm. In one study, 7 healthy men aged 67 to 75 and 7 aged 20 to 31 went 24 hours without water. The older men's blood became more concentrated and their antidiuretic hormone rose higher, yet they felt less thirsty and drank less, and afterwards their blood did not dilute back to where it had been. Their kidneys also could not concentrate urine as well as the younger men's (Phillips 1984). In other words, the alarm signal is still there, but both ends, thirst and the kidneys, have loosened.
So older people should not wait to feel thirsty before drinking. The older-adult nutrition guideline of the European Society for Clinical Nutrition and Metabolism (ESPEN) recommends offering older women at least 1.6 liters and older men at least 2.0 liters of drinks a day, unless a medical condition calls for something different. People whose doctor has limited their fluids for heart failure or kidney disease should follow their doctor (Volkert 2022). Keeping a cup within reach and drinking at set times, with meals and medicines, is more reliable than waiting for thirst.
In practice · How to tell if an older person drinks enough
Feeling whether the lips are dry, pinching the skin on the back of the hand to see if it springs back, and checking the color of the urine are all common checks, and none of them is reliable in older people. A systematic review of diagnostic accuracy, cited in the ESPEN guideline, found that no single sign consistently shows whether an older person is short of water. So the guideline says plainly that these signs should not be used to judge an older person's hydration (Volkert 2022).In hospital, whether an older person has been drinking too little is judged from a blood test of serum osmolality, a measure of how concentrated the blood is: above 300 mOsm/kg counts as dehydration (Volkert 2022).
So at home, what to watch is how much goes in, not whether someone looks dehydrated. Noting for a day or two how many times the cup is refilled and how much is drunk each time gives a fair picture; water, tea and milk all count as drinks.
Some situations make dehydration more likely and need extra attention: taking diuretics (medicines that make you pee more), diarrhea or vomiting, a fever, hot weather, and older people who rely on someone else to bring them drinks (NHS).
Chapter 4
Chewing and swallowing
Eating well starts with being able to chew and swallow.
With fewer teeth or dentures that do not fit, people quietly avoid foods that are hard to chew: raw vegetables and fruit, whole grains, pieces of meat. In a US national survey, people with all their natural teeth ate 2.1 times as many carrots and 1.5 times as much salad as people with full dentures, and more dietary fiber (Nowjack-Raymer 2003). This is an observed association, but it fits the mechanism: foods that cannot be chewed slowly disappear from the plate.
Swallowing is the next hurdle. Moving a mouthful from the mouth into the esophagus takes many muscles of the tongue and throat working in sequence while the entrance to the windpipe closes. In older people this swallowing response becomes slower and weaker, and food or drink can go down into the windpipe. This is called oropharyngeal dysphagia. It can lead to malnutrition, dehydration and aspiration pneumonia, yet it often goes unnoticed (Baijens 2016).
At the table, the food can adapt to the mouth: cut small, cooked soft, made into minced meat, steamed egg, tofu or stews. The ESPEN guideline recommends texture-modified food with added nutrients for older people who have chewing or swallowing problems and are not eating enough (Volkert 2022). But frequent coughing or choking while eating or drinking, a wet-sounding voice after meals, or a constant feeling that something is stuck in the throat is not solved by softer food: see a doctor soon (NHS).
With fewer teeth or dentures that do not fit, people quietly avoid foods that are hard to chew: raw vegetables and fruit, whole grains, pieces of meat. In a US national survey, people with all their natural teeth ate 2.1 times as many carrots and 1.5 times as much salad as people with full dentures, and more dietary fiber (Nowjack-Raymer 2003). This is an observed association, but it fits the mechanism: foods that cannot be chewed slowly disappear from the plate.
Swallowing is the next hurdle. Moving a mouthful from the mouth into the esophagus takes many muscles of the tongue and throat working in sequence while the entrance to the windpipe closes. In older people this swallowing response becomes slower and weaker, and food or drink can go down into the windpipe. This is called oropharyngeal dysphagia. It can lead to malnutrition, dehydration and aspiration pneumonia, yet it often goes unnoticed (Baijens 2016).
At the table, the food can adapt to the mouth: cut small, cooked soft, made into minced meat, steamed egg, tofu or stews. The ESPEN guideline recommends texture-modified food with added nutrients for older people who have chewing or swallowing problems and are not eating enough (Volkert 2022). But frequent coughing or choking while eating or drinking, a wet-sounding voice after meals, or a constant feeling that something is stuck in the throat is not solved by softer food: see a doctor soon (NHS).
Chapter 5
Absorbing less from the same food
From the same meal, an older body may take in less. The two clearest examples are vitamin B12 and vitamin D.
B12: the B12 in food is tightly bound to protein, and stomach acid and digestive enzymes have to strip it off first; Vitamin B12 explains this step. With age, the stomach lining often slowly wastes away and makes less acid, a condition called atrophic gastritis, and this step falters. A review reports that more than 20% of older people are short of B12, and that in more than six cases in ten the cause is exactly this: the B12 was eaten but never released from the food (Andrès 2004). Long-term use of acid-reducing medicines or metformin is also linked to low B12, as Drug–Nutrient Interactions explains in detail. The signs of low B12 are easy to miss: numb hands and feet, unsteady walking, a worsening memory and weakness, all easily put down to old age (NHS).
Vitamin D: the skin makes vitamin D from sunlight, using a cholesterol-like molecule in its outer layer as the raw material. Experiments on skin removed during surgery found that this raw material declines with age, and that under the same ultraviolet light, skin from people in their late 70s and early 80s made less than half as much vitamin D precursor as skin from children and young people (MacLaughlin 1985). Older people also go out less and show less skin, so they run short more easily.
Only a test can tell whether someone is short. What to take, and how much, is for a doctor to decide from the results.
B12: the B12 in food is tightly bound to protein, and stomach acid and digestive enzymes have to strip it off first; Vitamin B12 explains this step. With age, the stomach lining often slowly wastes away and makes less acid, a condition called atrophic gastritis, and this step falters. A review reports that more than 20% of older people are short of B12, and that in more than six cases in ten the cause is exactly this: the B12 was eaten but never released from the food (Andrès 2004). Long-term use of acid-reducing medicines or metformin is also linked to low B12, as Drug–Nutrient Interactions explains in detail. The signs of low B12 are easy to miss: numb hands and feet, unsteady walking, a worsening memory and weakness, all easily put down to old age (NHS).
Vitamin D: the skin makes vitamin D from sunlight, using a cholesterol-like molecule in its outer layer as the raw material. Experiments on skin removed during surgery found that this raw material declines with age, and that under the same ultraviolet light, skin from people in their late 70s and early 80s made less than half as much vitamin D precursor as skin from children and young people (MacLaughlin 1985). Older people also go out less and show less skin, so they run short more easily.
Only a test can tell whether someone is short. What to take, and how much, is for a doctor to decide from the results.
Evidence · Where the B12 and vitamin D figures come from
Where B12 deficiency comes from (Andrès 2004): among older people short of B12, more than six in ten have food-cobalamin malabsorption, meaning the B12 cannot be released from food or the gut lacks enough of the proteins that carry it. Between 15% and 20% have pernicious anemia, in which the immune system destroys intrinsic factor, the stomach protein that escorts B12. The rest come from eating too little and other absorption problems. The ESPEN guideline also states that atrophic gastritis impairs the absorption of B12, calcium and iron (Volkert 2022).Two common medicines: in a large case-control study, people who had used acid-reducing medicines (proton pump inhibitors) for 2 years or more had a higher risk of B12 deficiency; this is an observed association (Lam 2013). In the long-term follow-up of a diabetes prevention study, 4.3% of people on metformin for 5 years had low B12, against 2.3% on placebo (Aroda 2016). Neither medicine should be stopped on your own because of this; Drug–Nutrient Interactions explains how to get checked.
Skin making vitamin D (MacLaughlin 1985): researchers took skin removed during surgery from people aged 8 to 92, measured the raw material for vitamin D, and found it declined with age. Under ultraviolet light, skin from people aged 77 and 82 made less than half as much vitamin D precursor as skin from people aged 8 and 18. These were experiments on skin outside the body, not measurements in living people, but they point the same way as the US National Institutes of Health (NIH) Office of Dietary Supplements: older people make less vitamin D from sunlight (NIH ODS).
lam-2013-ppi-h2ra-b12-jamaaroda-2016-metformin-b12-dppos
Chapter 6
Adjusting meals to an older body
Each change in the chapters above points to one adjustment at the table. The most important is protein: eat enough, and spread it across every meal.
In older people, muscle responds less to the protein in a meal, which is called anabolic resistance. In pooled data, muscle building in young men reached its peak at about 0.24 g of protein per kilogram of body weight in a meal; older men needed about 0.40 g (Moore 2015). So do not pile all the protein into dinner: every meal should include a portion of egg, milk, tofu, fish or meat. How much to eat in a day is covered most fully in Sarcopenia; the ESPEN guideline's floor for older people is at least 1 g per kilogram of body weight a day (Volkert 2022).
With a small appetite and early fullness, eat small amounts more often: if a big bowl is too much, split the day into three main meals plus a few snacks. Adding egg, milk, tofu or a little oil to porridge, noodles or soup brings more energy and protein in the same mouthful. The ESPEN guideline recommends the same for older people who are not eating enough (Volkert 2022).
One point runs against intuition: do not restrict food without a reason. The guideline warns that dietary restrictions that make people eat less can harm older people and should generally be avoided (Volkert 2022). Whether a low-salt, low-fat or strict blood-sugar diet prescribed years ago still needs to be that strict is worth discussing again with a doctor, rather than dropping it all at once on your own.
In older people, muscle responds less to the protein in a meal, which is called anabolic resistance. In pooled data, muscle building in young men reached its peak at about 0.24 g of protein per kilogram of body weight in a meal; older men needed about 0.40 g (Moore 2015). So do not pile all the protein into dinner: every meal should include a portion of egg, milk, tofu, fish or meat. How much to eat in a day is covered most fully in Sarcopenia; the ESPEN guideline's floor for older people is at least 1 g per kilogram of body weight a day (Volkert 2022).
With a small appetite and early fullness, eat small amounts more often: if a big bowl is too much, split the day into three main meals plus a few snacks. Adding egg, milk, tofu or a little oil to porridge, noodles or soup brings more energy and protein in the same mouthful. The ESPEN guideline recommends the same for older people who are not eating enough (Volkert 2022).
One point runs against intuition: do not restrict food without a reason. The guideline warns that dietary restrictions that make people eat less can harm older people and should generally be avoided (Volkert 2022). Whether a low-salt, low-fat or strict blood-sugar diet prescribed years ago still needs to be that strict is worth discussing again with a doctor, rather than dropping it all at once on your own.
In practice · How to arrange a day of meals
Make the flavor count: once taste and smell have faded, building aroma with garlic, ginger, scallions, spices and vinegar is safer than adding more salt; the reason is in the chapter Taste and smell fade.Drink by the clock: keep a cup within reach and drink at set times, on getting up, with meals and with medicines, without waiting for thirst; the reason is in the chapter Not thirsty, yet short of water.
Start fiber with soft foods: constipation is common in older people. The ESPEN guideline uses about 25 g of dietary fiber a day as a reference value (Volkert 2022). Vegetables, beans and whole grains cooked soft and chopped small can be eaten even by people who struggle to chew. Where constipation comes from is covered in detail in Constipation.
Eat with someone: eating is something people do together, and older people often eat a little more when someone eats with them (Volkert 2022).
Work on the meals first: use the steps above first. If an older person still cannot eat enough and their weight keeps falling, a doctor or dietitian may prescribe oral nutritional supplements, such as nutrition powders or drinks (NHS). Do not buy a pile of supplements to stand in for meals. How to protect the bones is covered in detail in Osteoporosis.
Chapter 7
When an older parent needs a doctor
The situations below should not be written off as just getting old: take your parent to a doctor.
Weight and appetite:
Losing 5% to 10% or more of body weight over 3 to 6 months without trying, or clothes, belts and rings becoming loose (the UK National Health Service, NHS, lists this as the main sign of malnutrition).A poor appetite that lasts, together with constant tiredness, weakness or wounds that heal slowly.
Swallowing: frequent coughing or choking while eating or drinking, a wet-sounding voice after meals, a constant feeling that something is stuck in the throat, or repeated chest infections need a doctor's appointment soon.
Dehydration:
Peeing less, dark urine, dizziness on standing that does not go away, unusual tiredness, or fast breathing or heartbeat: see a doctor soon.Signs of dehydration together with confusion, being sleepier than usual or hard to wake, or cold skin, blue or gray lips or skin, or difficulty breathing: call emergency services now, because this may be shock.
Possible low B12: numbness or pins and needles in the hands and feet, unsteady walking, or a worsening memory should be checked by a doctor; left too long, some of the damage may not reverse.
Medicines: if your parent takes several medicines at once, or loses their appetite or their sense of taste after starting a new one, take every medicine box to a doctor or pharmacist, and do not stop any medicine on your own.
The ESPEN guideline recommends regular malnutrition screening for older people, and you can ask the doctor to do one at an appointment (Volkert 2022). This story is education and does not replace a diagnosis.
Weight and appetite:
Losing 5% to 10% or more of body weight over 3 to 6 months without trying, or clothes, belts and rings becoming loose (the UK National Health Service, NHS, lists this as the main sign of malnutrition).A poor appetite that lasts, together with constant tiredness, weakness or wounds that heal slowly.
Swallowing: frequent coughing or choking while eating or drinking, a wet-sounding voice after meals, a constant feeling that something is stuck in the throat, or repeated chest infections need a doctor's appointment soon.
Dehydration:
Peeing less, dark urine, dizziness on standing that does not go away, unusual tiredness, or fast breathing or heartbeat: see a doctor soon.Signs of dehydration together with confusion, being sleepier than usual or hard to wake, or cold skin, blue or gray lips or skin, or difficulty breathing: call emergency services now, because this may be shock.
Possible low B12: numbness or pins and needles in the hands and feet, unsteady walking, or a worsening memory should be checked by a doctor; left too long, some of the damage may not reverse.
Medicines: if your parent takes several medicines at once, or loses their appetite or their sense of taste after starting a new one, take every medicine box to a doctor or pharmacist, and do not stop any medicine on your own.
The ESPEN guideline recommends regular malnutrition screening for older people, and you can ask the doctor to do one at an appointment (Volkert 2022). This story is education and does not replace a diagnosis.
References · 18
- Landi, F., Calvani, R., Tosato, M., Martone, A. M., Ortolani, E., Savera, G., Sisto, A., & Marzetti, E. (2016). Anorexia of aging: Risk factors, consequences, and potential treatments. Nutrients, 8(2), 69. Narrative review. Anorexia of aging is a decrease in appetite and/or food intake in old age and a major contributor to undernutrition; it is not an unavoidable consequence of aging, but advancing age often promotes it through several mechanisms, and changes in lifestyle, disease, and social and environmental factors also affect eating. Simple interventions such as oral nutritional supplements or modified diets could meaningfully improve health and quality of life. 10.3390/nu8020069
- Clarkston, W. K., Pantano, M. M., Morley, J. E., Horowitz, M., Littlefield, J. M., & Burton, F. R. (1997). Evidence for the anorexia of aging: Gastrointestinal transit and hunger in healthy elderly vs. young adults. American Journal of Physiology, 272(1 Pt 2), R243-R248. Cross-sectional comparison of 19 young (23-50 years) and 14 elderly (70-84 years) healthy volunteers. After a meal the elderly had less desire to eat and less hunger, but not significantly greater fullness. Gastric 50% emptying time was slower in the elderly for solids (182 vs 127 min) and liquids (47 vs 35 min); postprandial hunger was inversely related to solid gastric emptying (r = -0.39). Orocecal and total gut transit did not differ. Autonomic function was abnormal in 11 elderly and no young subjects. Conclusion: slower gastric emptying may contribute to anorexia in aging. 10.1152/ajpregu.1997.272.1.R243
- Johnson, K. O., Shannon, O. M., Matu, J., Holliday, A., Ispoglou, T., & Deighton, K. (2020). Differences in circulating appetite-related hormone concentrations between younger and older adults: A systematic review and meta-analysis. Aging Clinical and Experimental Research, 32(7), 1233-1244. Thirty-five studies, 710 healthy older adults (mean age 73) and 713 younger adults (mean age 28). Older adults had higher fasted and postprandial cholecystokinin (SMD 0.41 both), higher leptin and higher postprandial insulin, a non-significant trend to higher postprandial peptide YY, lower energy intake (SMD -0.98) and lower fasted hunger (SMD -1.00). Conclusion: higher insulin, leptin, cholecystokinin and peptide YY accord with reduced appetite and energy intake in healthy older adults. Ghrelin is not among the reported differences. 10.1007/s40520-019-01292-6
- Roberts, S. B., Fuss, P., Heyman, M. B., Evans, W. J., Tsay, R., Rasmussen, H., Fiatarone, M., Cortiella, J., Dallal, G. E., & Young, V. R. (1994). Control of food intake in older men. JAMA, 272(20), 1601-1606. Dietary intervention study in 35 healthy younger and older men of normal weight, overfed (n = 17) or underfed (n = 18) for 21 days, then free to eat. Aging did not change the weight, body composition or energy expenditure response to the feeding period itself. Afterwards, younger men spontaneously ate less after overfeeding and more after underfeeding and returned to their weight; older men did neither, so they kept the weight gained or failed to regain the weight lost. Conclusion: aging may impair the control of food intake after over- or undereating, which may help explain unexplained weight loss and gain in older people. Small study in men only. 10.1001/jama.1994.03520200057036
- Volkert, D., Beck, A. M., Cederholm, T., Cruz-Jentoft, A., Hooper, L., Kiesswetter, E., Maggio, M., Raynaud-Simon, A., Sieber, C., Sobotka, L., van Asselt, D., Wirth, R., & Bischoff, S. C. (2022). ESPEN practical guideline: Clinical nutrition and hydration in geriatrics. Clinical Nutrition, 41(4), 958-989. Eighty-two recommendations (full text). Energy guiding value about 30 kcal/kg/day, individually adjusted; protein at least 1 g/kg/day. Older women should be offered at least 1.6 L and men at least 2.0 L of drinks a day unless a clinical condition requires otherwise; heart and renal failure may need fluid restriction. All older persons should be screened for malnutrition with a validated tool. Atrophic gastritis impairs absorption of vitamin B12, calcium and iron; micronutrients follow recommendations for healthy older persons unless there is a deficiency. Dietary restrictions that may limit intake are potentially harmful and should be avoided. Eating in company stimulates intake. Those at risk of malnutrition should be offered fortified food, additional snacks or finger food, and, with chewing or swallowing problems, texture-modified enriched food; oral nutritional supplements when counseling and food modification are not enough. All older persons should be considered at risk of low-intake dehydration; directly measured serum osmolality above 300 mOsm/kg identifies it, while simple signs such as skin turgor, mouth dryness, weight change and urine color shall not be used to assess hydration in older adults. 10.1016/j.clnu.2022.01.024
- NHS. (2026). Dehydration. Babies, children and older adults are more at risk; it happens more easily in people who take diuretics or rely on other people to get them drinks. Ask for an urgent GP appointment or call NHS 111 for unusual tiredness, dizziness on standing that does not go away, dark yellow urine or peeing less than normal, or fast breathing or heart rate. Call 999 or go to A&E if someone with signs of dehydration has blue, grey, pale or blotchy skin, lips or tongue, cold skin, difficulty breathing, is confused, or is sleepier than normal or difficult to wake; these could be signs of shock (page last reviewed 1 May 2026). www.nhs.uk/conditions/dehydration
- Doty, R. L., Shaman, P., Applebaum, S. L., Giberson, R., Siksorski, L., & Rosenberg, L. (1984). Smell identification ability: Changes with age. Science, 226(4681), 1441-1443. Cross-sectional smell identification testing in 1955 people aged 5 to 99. Women outperformed men and nonsmokers outperformed smokers at all ages. Performance peaked in the third to fifth decades and declined markedly after the seventh. More than half of those aged 65 to 80, and more than three-quarters of those over 80, had major olfactory impairment. The authors note this fits elderly complaints that food lacks flavor and their excess of accidental gas poisoning. 10.1126/science.6505700
- Schiffman, S. S. (1997). Taste and smell losses in normal aging and disease. JAMA, 278(16), 1357-1362. Review of MEDLINE literature 1966-1997. Losses of taste and smell are common in the elderly and come from normal aging, certain diseases (especially Alzheimer disease), medications, surgery and environmental exposure. They reduce the pleasure and comfort of food, are risk factors for nutritional and immune deficiencies and for poor adherence to specific diets, and can lead to food poisoning or overexposure to hazardous chemicals. Flavor-enhanced food can increase enjoyment of food and has a positive effect on food intake and immune status. 10.1001/jama.1997.03550160077042
- Phillips, P. A., Rolls, B. J., Ledingham, J. G., Forsling, M. L., Morton, J. J., Crowe, M. J., & Wollner, L. (1984). Reduced thirst after water deprivation in healthy elderly men. The New England Journal of Medicine, 311(12), 753-759. Seven healthy active men aged 67 to 75 and seven aged 20 to 31, matched for weight loss, went 24 hours without water. The older men had greater rises in plasma osmolality, sodium and vasopressin, but lower urine osmolality; they were less thirsty and drank less afterwards, so their plasma and urine did not return to pre-deprivation levels. Conclusion: a deficit in thirst and water intake in healthy elderly men although vasopressin responsiveness is maintained or increased; the age-related deficit in urine concentrating ability reflects renal causes, not a lack of vasopressin. 10.1056/NEJM198409203111202
- Nowjack-Raymer, R. E., & Sheiham, A. (2003). Association of edentulism and diet and nutrition in US adults. Journal of Dental Research, 82(2), 123-126. Cross-sectional analysis of NHANES III. After adjusting for social and behavioral factors, people with no teeth wearing complete dentures ate carrots 2.1 times less and tossed salads 1.5 times less than people with all their natural teeth, and 1.2 times less dietary fiber; their serum beta carotene, folate and vitamin C were also lower. Observational association. 10.1177/154405910308200209
- Baijens, L. W., Clavé, P., Cras, P., Ekberg, O., Forster, A., Kolb, G. F., Leners, J.-C., Masiero, S., Mateos-Nozal, J., Ortega, O., Smithard, D. G., Speyer, R., & Walshe, M. (2016). European Society for Swallowing Disorders - European Union Geriatric Medicine Society white paper: Oropharyngeal dysphagia as a geriatric syndrome. Clinical Interventions in Aging, 11, 1403-1428. Position paper. Oropharyngeal dysphagia is impaired or uncomfortable transit of food or liquid from the mouth to the esophagus. It can cause malnutrition, dehydration, respiratory infections and aspiration pneumonia. It is prevalent among older patients because the oropharyngeal swallow response is impaired in older people and can cause aspiration; it is underdiagnosed, is diagnosed by validated clinical and instrumental methods, and is treated mainly with compensatory measures. It should be in standard screening protocols. 10.2147/CIA.S107750
- NHS. (2023). Dysphagia (swallowing problems). Signs include coughing or choking when eating or drinking, bringing food back up sometimes through the nose, a feeling that food is stuck, and a gurgly, wet-sounding voice when eating or drinking; over time it can cause weight loss, dehydration and repeated chest infections. Ask for an urgent GP appointment or get help from NHS 111 if you or your child has difficulty swallowing, coughs or chokes while eating or drinking, feels something is stuck in the throat after eating, keeps bringing food or milk back up sometimes through the nose, cries a lot or arches their back when feeding, has a wet, gurgly voice after eating or drinking, is short of breath after eating or drinking, or gets lots of chest infections (page last reviewed 2 May 2023). www.nhs.uk/symptoms/swallowing-problems-dysphagia
- Andrès, E., Loukili, N. H., Noel, E., Kaltenbach, G., Abdelgheni, M. B., Perrin, A. E., Noblet-Dick, M., Maloisel, F., Schlienger, J.-L., & Blicklé, J.-F. (2004). Vitamin B12 (cobalamin) deficiency in elderly patients. CMAJ, 171(3), 251-259. Review. Cobalamin deficiency is frequent (over 20%) among elderly people and often unrecognized because its signs are subtle, yet potentially serious (neuropsychiatric and hematological). Causes: food-cobalamin malabsorption (over 60% of cases), pernicious anemia (15-20%), insufficient intake and malabsorption. Food-cobalamin malabsorption is the inability to release cobalamin from food or a deficiency of intestinal cobalamin transport proteins, or both. 10.1503/cmaj.1031155
- NHS. (2023). Vitamin B12 or folate deficiency anaemia: symptoms. Symptoms usually develop gradually and include feeling weak or tired, shortness of breath, headaches, palpitations, a sore or red tongue sometimes with mouth ulcers, and problems with memory; vitamin B12 deficiency can also cause neurological symptoms including numbness, pins and needles, muscle weakness, and problems with balance and coordination. See a GP if you have these symptoms; diagnosis and treatment as soon as possible matters, because some problems can be irreversible if left untreated. www.nhs.uk/conditions/vitamin-b12-or-folate-deficiency-anaemia/symptoms
- MacLaughlin, J., & Holick, M. F. (1985). Aging decreases the capacity of human skin to produce vitamin D3. The Journal of Clinical Investigation, 76(4), 1536-1538. Surgically obtained skin from people aged 8 to 92 showed an age-dependent decrease in epidermal provitamin D3 (7-dehydrocholesterol). Samples exposed to ultraviolet radiation: the epidermis made more than 80% of the previtamin D3, and skin from 77- and 82-year-olds made less than half as much previtamin D3 as skin from 8- and 18-year-olds. The authors note this matters for elderly people who expose little skin to sunlight. Skin samples studied outside the body. 10.1172/JCI112134
- National Institutes of Health, Office of Dietary Supplements. (2024). Vitamin D — Fact Sheet for Health Professionals. Fact sheet (updated June 27, 2025; Wayback snapshot 20 September 2026): 25(OH)D below 30 nmol/L (12 ng/mL) is associated with deficiency, 30 to below 50 nmol/L is generally considered inadequate, 50 nmol/L (20 ng/mL) or more is sufficient for most people, and above 125 nmol/L (50 ng/mL) can be associated with adverse effects; RDA 600 IU (15 mcg) to age 70 and 800 IU (20 mcg) above 70; adult UL 4,000 IU (100 mcg); older people and people with darker skin (more melanin) make less vitamin D from sunlight (fact sheet). ods.od.nih.gov/factsheets/VitaminD-HealthProfessional
- Moore, D. R., Churchward-Venne, T. A., Witard, O., Breen, L., Burd, N. A., Tipton, K. D., & Phillips, S. M. (2015). Protein ingestion to stimulate myofibrillar protein synthesis requires greater relative protein intakes in healthy older versus younger men. Journal of Gerontology Series A: Biological Sciences and Medical Sciences, 70(1), 57-62. Retrospective breakpoint analysis of pooled dose-response data: myofibrillar protein synthesis plateaued after 0.24 g/kg body mass in younger men versus 0.40 g/kg in older men (0.25 vs 0.60 g/kg lean body mass), i.e. older men need a greater relative per-meal protein dose. 10.1093/gerona/glu103
- NHS. (2023). Malnutrition (overview and symptoms). The main sign is unintentional weight loss: losing 5 to 10% or more of body weight over 3 to 6 months; clothes, belts and jewellery becoming looser; a BMI under 18.5. Other symptoms: reduced appetite, lack of interest in food and drink, tiredness, weakness, getting ill often and recovering slowly, wounds healing slowly, poor concentration and feeling cold. People aged 65 and over are particularly at risk, and weight loss is not an inevitable result of old age. See a GP after unintentional weight loss over 3 to 6 months or if worried that an older person in your care may be malnourished. First dietary advice: fortified high-calorie, high-protein foods, snacks between meals and nourishing drinks; nutritional drinks or supplements if that is not enough (page last reviewed 23 May 2023). www.nhs.uk/conditions/malnutrition