Calcium co-ingestion augments postprandial glucose-dependent insulinotropic peptide1–42, glucagon-like peptide-1 and insulin concentrations in humans

Purpose

This study determined whether calcium co-ingestion potentiates postprandial GIP_1–42 and GLP-1 concentrations in humans and the concomitant impact on insulin, appetite sensations and substrate metabolism.

Methods

Ten healthy males consumed two energy- and macronutrient-matched meals in a double-blind, randomized, crossover design. The calcium content of the control meal was 3 mg/kg body mass, which was increased to 15 mg/kg body mass with calcium co-ingestion. Circulating concentrations of GIP_1–42, GLP-1 and insulin were determined over a 180-min postprandial period, followed by 60 min of exercise. Visual analogue scales were used to determine subjective appetite sensations. Rates of energy expenditure and substrate (lipid and carbohydrate) oxidation were estimated using indirect calorimetry.

Results

Calcium co-ingestion resulted in a 47 % increase in GIP_1–42, a 22 % increase in GLP-1 and a 19 % increase in insulin areas under the curve for the 120 min following consumption (all P < 0.05). Furthermore, appetite sensations were suppressed by calcium co-ingestion by 12 % (P = 0.034). No differences, however, were observed in substrate metabolism (P > 0.05).

Conclusion

Ingestion of a high-calcium meal potentiates postprandial GIP_1–42, GLP-1 and insulin concentrations in humans. Subjective appetite is also temporarily suppressed, although substrate metabolism is unaffected.     

Long-term cysteine fortification impacts cysteine/glutathione homeostasis and food intake in ageing rats

Purpose

Healthy ageing is associated with higher levels of glutathione. The study aimed to determine whether long-term dietary fortification with cysteine increases cysteine and glutathione pools, thus alleviating age-associated low-grade inflammation and resulting in global physiological benefits.

Methods

The effect of a 14-week dietary fortification with cysteine was studied in non-inflamed (NI, healthy at baseline) and in spontaneously age-related low-grade inflamed (LGI, prefrail at baseline) 21-month-old rats. Fifty-seven NI rats and 14 LGI rats received cysteine-supplemented diet (4.0 g/kg of free cysteine added to the standard diet containing 2.8 g/kg cysteine). Fifty-six NI rats and 16 LGI rats received a control alanine-supplemented diet.

Results

Cysteine fortification in NI rats increased free cysteine (P < 0.0001) and glutathione (P < 0.03) in the liver and the small intestine. In LGI rats, cysteine fortification increased total non-protein cysteine (P < 0.0007) and free cysteine (P < 0.03) in plasma, and free cysteine (P < 0.02) and glutathione (P < 0.01) in liver. Food intake decreased over time in alanine-fed rats (r ² = 0.73, P = 0.0002), whereas it was constant in cysteine-fed rats (r ² = 0.02, P = 0.68). Cysteine fortification did not affect inflammatory markers, mortality, body weight loss, or tissue masses.

Conclusion

Doubling the dietary intake of cysteine in old rats increased cysteine and glutathione pools in selected tissues. Additionally, it alleviated the age-related decline in food intake. Further validation of these effects in the elderly population suffering from age-related anorexia would suggest a useful therapeutic approach to the problem.     

Whey protein consumption after resistance exercise reduces energy intake at a post-exercise meal

Purpose

Protein consumption after resistance exercise potentiates muscle protein synthesis, but its effects on subsequent appetite in this context are unknown. This study examined appetite and energy intake following consumption of protein- and carbohydrate-containing drinks after resistance exercise.

Methods

After familiarisation, 15 resistance training males (age 21 ± 1 years, body mass 78.0 ± 11.9 kg, stature 1.78 ± 0.07 m) completed two randomised, double-blind trials, consisting of lower-body resistance exercise, followed by consumption of a whey protein (PRO 23.9 ± 3.6 g protein) or dextrose (CHO 26.5 ± 3.8 g carbohydrate) drink in the 5 min post-exercise. An ad libitum meal was served 60 min later, with subjective appetite measured throughout. Drinks were flavoured and matched for energy content and volume. The PRO drink provided 0.3 g/kg body mass protein.

Results

Ad libitum energy intake (PRO 3742 ± 994 kJ; CHO 4172 ± 1132 kJ; P = 0.007) and mean eating rate (PRO 339 ± 102 kJ/min; CHO 405 ± 154 kJ/min; P = 0.009) were lower during PRO. The change in eating rate was associated with the change in energy intake (R = 0.661, P = 0.007). No interaction effects were observed for subjective measures of appetite. The PRO drink was perceived as creamier and thicker, and less pleasant, sweet and refreshing (P < 0.05).

Conclusion

These results suggest whey protein consumption after resistance exercise reduces subsequent energy intake, and this might be partially mediated by a reduced eating rate. Whilst this reduced energy intake is unlikely to impair hypertrophy, it may be of value in supporting an energy deficit for weight loss.

     

Combined medium-chain triglyceride and chilli feeding increases diet-induced thermogenesis in normal-weight humans

Background and purpose

Capsaicin, the active ingredient of chilli, and medium-chain triglycerides (MCT) have been shown to increase diet-induced thermogenesis (DIT), improve satiety and decrease energy intake. Combinations of thermogenic ingredients have previously been investigated such as mustard and chilli, or capsaicin and green tea with positive effects. The aim of this study was to investigate the combined effects of chilli and MCT feeding on DIT and satiety in healthy volunteers.

Methods

Seven healthy volunteers were tested on four occasions following an overnight fast. Volunteers were fed a breakfast containing chilli and MCT oil, chilli and sunflower oil, bell pepper and sunflower oil or bell pepper and MCT oil. Satiety and gastrointestinal comfort were measured using visual analogue scales (VAS) and category scales. Baseline energy expenditure, and DIT and fat oxidation were measured for 6 h using indirect calorimetry.

Results

There were significant differences in DIT between the meals (P = 0.003) which increased from 7.0 % for pepper–sunflower oil to 10.7 % for chilli–MCT oil. The predominant differences existed between the chilli–MCT oil and chilli–sunflower oil (P = 0.013), between chilli–MCT oil and pepper–sunflower oil (P = 0.007) and between pepper–sunflower oil and pepper–MCT oil (P = 0.004). There was a significant difference in fat oxidation between the pepper–sunflower oil and pepper–MCT oil (P = 0.032). There were no differences in any VAS satiety parameters or gastrointestinal comfort ratings.

Conclusion

Adding chilli and MCT to meals increases DIT by over 50 % which over time may cumulate to help induce weight loss and prevent weight gain or regain.     

Dietary factors associated with metabolic risk score in Finnish children aged 6–8 years: the PANIC study

Purpose

Previous evidence for the associations of eating frequency and food consumption with clustering of metabolic risk factors among children is limited. We therefore investigated association of the daily number of main meals and snacks and food consumption with a metabolic risk score and individual metabolic risk factors in primary school children.

Methods

The subjects were a population sample of Finnish girls and boys 6–8 years of age. Dietary factors were measured by a four-day food record. Metabolic risk score was calculated summing up the Z-scores of waist circumference, systolic and diastolic blood pressure, and concentrations of fasting serum insulin and fasting plasma glucose, triglycerides and high-density lipoprotein cholesterol, the latest multiplying by ?1.

Results

Skipping main meals (standardized regression coefficient β = ?0.18, P < 0.001), a higher consumption of non-root vegetables (β = 0.18, P < 0.01), low-fat vegetable-oil-based margarine (β = 0.13, P < 0.01) and sugar-sweetened beverages (β = 0.11, P < 0.05) and a lower consumption of vegetable oils (β = ?0.10, P < 0.05) were associated with a higher metabolic risk score after adjustment for age, sex, total physical activity, electronic media time, energy intake and other dietary factors. The consumption of red meat was directly related to the metabolic risk score, but the association was not statistically significant after adjustment for energy intake.

Conclusions

Eating main meals regularly, decreasing the consumption of sugar-sweetened beverages and low-fat margarine and increasing the consumption of vegetable oils should be emphasized to reduce metabolic risk among children.     

Variation in the effects of three different breakfast meals on subjective satiety and subsequent intake of energy at lunch and evening meal

Purpose

To determine the relative impact of three iso-caloric breakfast meals, of variable composition, on satiety, hunger and subsequent intake of energy.

Methods

In a three-way, crossover design, 30 healthy men (age of 21.7 ± 1.2 years; BMI, 23.1 ± 2.7 kg/m²) were randomised to one of three test breakfasts, on three separate occasions, separated by 1 week. The breakfasts consisted of eggs on toast, cereal (cornflakes) with milk and toast, or a croissant and orange juice. Subjective ratings of satiety, hunger, fullness and desire to eat were recorded at 30-min intervals by electronic visual analogue scales (VAS). Energy intake was assessed by weighed food intake at an ad libitum lunch and evening meal.

Results

Participants showed increased satiety, less hunger and a lower desire to eat after the breakfast containing eggs relative to the cereal (p < 0.02), and croissant-based meals (p < 0.0001). The egg breakfast was also accompanied by a significantly lower intake of energy relative to the croissant- and cereal-based breakfasts at the buffet lunch and evening meal, respectively, 1,284 ± 464 (egg) versus 1,442 ± 426 kcal (croissant), p = 0.03, 1,407 ± 379 (cereal) at lunch and 1,899 ± 729 (egg) versus 2,214 ± 620 kcal (cereal), p = 0.02, 2,047 ± 712 (croissant) at evening meal. The breakfast meal with the greatest effect on satiety and subsequent intake of energy was distinct in having the highest protein and lowest carbohydrate content relative to the other two breakfasts.

Conclusion

These findings provide evidence to support the importance of food choice at breakfast as a means of increasing satiety in the morning and reducing energy intake at lunch.     

Serum leptin and total dietary energy intake: the INTERLIPID Study

Purpose

It has been hypothesized that leptin-induced appetite suppression is impaired in obese individuals, but little human evidence is available documenting this. We investigated relations between serum leptin and total energy intake using INTERLIPID/INTERMAP data on Japanese–Americans in Hawaii and Japanese in Japan.

Methods

Serum leptin and nutrient intakes were examined by standardized methods in men and women aged 40–59 years from two population samples, one Japanese–American in Hawaii (88 men, 94 women), the other Japanese in central Japan (123 men, 111 women). Multiple linear regression analyses stratified by BMI category (<25 kg/m², 25–29.9 kg/m², and ≥30 kg/m²) with adjustment for possible confounders were used to examine the relation between log-leptin and total dietary energy intake.

Results

In multivariate regression analyses, in those with BMI < 25 kg/m² and in those with BMI between 25 and 29.9 kg/m², log-leptin was not significantly related to total dietary energy intake; in those with BMI ≥ 30 kg/m², it was significantly inversely related to total dietary energy intake (P = 0.029), independent of body weight and physical activity. Physical activity score was significantly positively related to total dietary energy intake only in participants with BMI < 25 kg/m² (P < 0.001).

Conclusion

Leptin was significantly inversely associated with dietary energy intake in obese persons, but not in overweight and normal-weight persons.     

Disturbed eating at high altitude: influence of food preferences, acute mountain sickness and satiation hormones

Purpose

Hypoxia has been shown to reduce energy intake and lead to weight loss, but the underlying mechanisms are unclear. The aim was therefore to assess changes in eating after rapid ascent to 4,559 m and to investigate to what extent hypoxia, acute mountain sickness (AMS), food preferences and satiation hormones influence eating behavior.

Methods

Participants (n = 23) were studied at near sea level (Zurich (ZH), 446 m) and on two days after rapid ascent to Capanna Margherita (MG) at 4,559 m (MG2 and MG4). Changes in appetite, food preferences and energy intake in an ad libitum meal were assessed. Plasma concentrations of cholecystokinin, peptide tyrosine–tyrosine, gastrin, glucagon and amylin were measured. Peripheral oxygen saturation (SpO₂) was monitored, and AMS assessed using the Lake Louis score.

Results

Energy intake from the ad libitum meal was reduced on MG2 compared to ZH (643 ± 308 vs. 952 ± 458 kcal, p = 0.001), but was similar to ZH on MG4 (890 ± 298 kcal). Energy intake on all test days was correlated with hunger/satiety scores prior to the meal and AMS scores on MG2 but not with SpO₂ on any of the 3 days. Liking for high-fat foods before a meal predicted subsequent energy intake on all days. None of the satiation hormones showed significant differences between the 3 days.

Conclusion

Reduced energy intake after rapid ascent to high altitude is associated with AMS severity. This effect was not directly associated with hypoxia or changes in gastrointestinal hormones. Other peripheral and central factors appear to reduce food intake at high altitude.     

Effect of dietary fatty acid composition on substrate utilization and body weight maintenance in humans

Background/purpose

Dietary fat content is a primary factor associated with the increase in global obesity rates. There is a delay in achieving fat balance following exposure to a high-fat (HF) diet (≥ 40 % of total energy from fat) and fat balance is closely linked to energy balance. Exercise has been shown to improve this rate of adaptation to a HF diet. Recently, however, the role of dietary fatty acid composition on energy and macronutrient balance has come into question.

Methods

We chose studies that compared monounsaturated fatty acids (MUFA), polyunsaturated fatty acids (PUFA), and saturated fatty acids (SFA). We have reviewed studies that measured diet-induced thermogenesis (DIT), energy expenditure (EE), or fat oxidation (FOx) in response to a HF meal challenge, or long-term dietary intervention comparing these fatty acids.

Results

While single-meal studies show that SFA induce lower DIT and FOx compared to unsaturated fats, the effect of the degree of unsaturation (MUFA vs. PUFA) appears to yet be determined. Long-term dietary interventions also support the notion that unsaturated fats induce greater EE, DIT, and/or FOx versus SFA and that a high MUFA diet induces more weight loss compared to a high SFA diet. Sex and BMI status also affect the metabolic responses to different fatty acids; however, more research in these areas is warranted.

Conclusion

SFA are likely more obesigenic than MUFA, and PUFA. The unsaturated fats appear to be more metabolically beneficial, specifically MUFA ≥ PUFA > SFA, as evidenced by the higher DIT and FOx following HF meals or diets.     

Dietary intake of energy and nutrients in relation to resting energy expenditure and anthropometric parameters of Czech pregnant women

Purpose

The aim of this study was to evaluate the dietary intake of energy and nutrients (DIEN) of Czech pregnant women and to assess relationships with body size variables during pregnancy.

Methods

One hundred and fifty-two randomly recruited healthy pregnant Czech women, who were normoglycemic, euthyroid, nonsmokers, not anemic, and not users of chronic medications or abusers of alcohol or drugs from countryside and city with different education, were recruited for the study. Anthropometric parameters were measured and resting energy expenditure obtained by indirect calorimetry after 12 h of fasting during four phases of pregnancy. DIEN was evaluated from self-reported dietary intake records over 7 days.

Results

Positive correlations were demonstrated between measured resting energy expenditure and intake of energy, substrates and some minerals and vitamins, and negative correlations between DIEN and anthropometric parameters. Lower dietary intake of energy and differences between dietary intake of nutrients and recommended daily allowances during pregnancy of Czech women were documented.

Conclusions

The difference between pregnancy body weight and ideal body weight was shown to be a determinant of DIEN. From recent knowledge on prevention of various pathological states, the supplementation or modification of nutritional intake of food with folate, iron, vitamin D, zinc, iodine and fiber for Czech pregnant women is recommended.     

Effects of Timing of Whey Protein Intake on Appetite and Energy Intake in Healthy Older Men

Background

Protein-rich supplements are used widely to prevent and manage malnutrition in older adults. We previously showed that 30 g whey protein ingestion, 3 hours before a buffet meal, suppressed energy intake in young, but not in older men. Information about the impact of the timing of ingestion of protein drinks on the suppression of energy intake in older adults is lacking.

Polydextrose: its impact on short-term food intake and subjective feelings of satiety in males—a randomized controlled cross-over study

Purpose

Polydextrose is a low-calorie highly branched-chain glucose polymer that is poorly digested in the upper gastrointestinal tract and therefore demonstrates fibre-like properties. Fibre has been shown to increase satiety and possibly reduce food intake. Therefore, the objective of the current study was to examine the effects of polydextrose on short-term satiety and energy intake.

Methods

In a repeated-measures randomized blind cross-over design, 26 healthy males consumed a 400-g fruit smoothie containing 12 g (3 %) of polydextrose, and a buffet lunch 60 min after the smoothie. Motivational ratings for satiety and palatability and lunch energy intake were measured. The effects of the polydextrose-containing smoothie were compared against a polydextrose-free control smoothie.

Results

Polydextrose did not significantly alter the taste and palatability of the fruit smoothie. Consuming the polydextrose-containing smoothie resulted in a significantly lower energy intake at lunch (102 kcal less) compared to the control.

Conclusion

Polydextrose may be a good fortificant for reducing short-term food intake.     

A PUFA-rich diet improves fat oxidation following saturated fat-rich meal

Purpose

To determine substrate oxidation responses to saturated fatty acid (SFA)-rich meals before and after a 7-day polyunsaturated fatty acid (PUFA)-rich diet versus control diet.

Methods

Twenty-six, normal-weight, adults were randomly assigned to either PUFA or control diet. Following a 3-day lead-in diet, participants completed the pre-diet visit where anthropometrics and resting metabolic rate (RMR) were measured, and two SFA-rich HF meals (breakfast and lunch) were consumed. Indirect calorimetry was used to determine fat oxidation (Fox) and energy expenditure (EE) for 4 h after each meal. Participants then consumed a PUFA-rich diet (50 % carbohydrate, 15 % protein, 35 % fat, of which 21 % of total energy was PUFA) or control diet (50 % carbohydrate, 15 % protein, 35 % fat, of which 7 % of total energy was PUFA) for the next 7 days. Following the 7-day diet, participants completed the post-diet visit.

Results

From pre- to post-PUFA-rich diet, there was no change in RMR (16.3 ± 0.8 vs. 16.4 ± 0.8 kcal/20 min) or in incremental area under the curve for EE (118.9 ± 20.6–126.9 ± 14.1 kcal/8h, ns). Fasting respiratory exchange ratio increased from pre- to post-PUFA-rich diet only (0.83 ± 0.1–0.86 ± 0.1, p < 0.05). The postprandial change in Fox increased from pre- to post-visit in PUFA-rich diet (0.03 ± 0.1–0.23 ± 0.1 g/15 min for cumulative Fox; p < 0.05), whereas controls showed no change.

Conclusions

Adopting a PUFA-rich diet initiates greater fat oxidation after eating occasional high SFA meals compared to a control diet, an effect achieved in 7 days.

     

Acute effects of high-protein versus normal-protein isocaloric meals on satiety and ghrelin

Purpose

The objective was to compare isocaloric high-protein (HP) test meals with normal-protein (NP) test ones on satiety and ghrelin in human being.

Methods

Systematic searches were conducted by using PubMed, Cochrane library, EMBASE, and HighWire Press to identify randomized, crossover trials that investigated the acute effects of isocalorically prescribed HP versus NP test meals on satiety and ghrelin.

Results

Pooled analyses showed that subjects with HP test meals had a significantly higher acute satiety area under the curve (AUC) than those with NP test meals (P < 0.001). Conversely, the former had a markedly lower level of acute ghrelin at 180 min as well as acute glucose AUC, although they had a notably higher glucose at 180 min (P = 0.008).

Conclusions

The meta-analysis showed that the acute consumption of HP did produce more satiety. In addition, relative to NP test meals, HP test ones may be useful in regulating postprandial glucose, whereas a significantly higher preprandial glucose combined with a lower concentration of ghrelin may contribute to the decrease in ad libitum caloric intake.     

Protein-Enriched Bread and Readymade Meals Increase Community-Dwelling Older Adults' Protein Intake in a Double-Blind Randomized Controlled Trial

Objectives

Sufficient protein intake can decrease undernutrition risk among community-dwelling older adults. This study aimed to increase community-dwelling older adults' daily protein intake with acceptable and applicable protein-enriched bread and readymade meals at home.

The effect of submicron fat droplets in a drink on satiety,food intake,and cholecystokinin in healthy volunteers

Purpose

Small fat droplets infused into the gut reduce food intake and hunger more than bigger ones, at levels as low as 6 g, and these effects are hypothesized to occur via satiety hormones such as cholecystokinin. It is, however, unknown whether the effect of droplet size would persist after oral consumption. It is also unknown whether an even smaller droplet size can affect hunger and food intake and at what minimum amount of fat. Therefore, the aim of the study was to test the effect of very fine fat droplets on satiety and food intake in two different quantities.

Methods

In a balanced-order 4-way crossover design, 24 volunteers consumed a fat-free meal replacement drink with either 5 or 9 g oil (rapeseed) and either 3 or 0.1 μm droplet size. Appetite scores and plasma cholecystokinin levels (in n = 12 subset) were measured for 180 min, when food intake was assessed during an ad libitum meal. Data were analyzed by ANCOVA, followed by Dunnett’s test and paired t test. The behavior of the emulsions was also characterized in a simulated gastrointestinal model.

Results

Despite faster in vitro lipolysis of the smallest droplets, neither droplet size nor fat amount affected satiety or food intake. From t = 45–150 min, cholecystokinin response was 50 % higher (P < 0.05) after the 0.1 versus 3 μm, but only with 9 g fat.

Conclusion

When this particular fat at these amounts is delivered in a meal replacement drink, droplet size does not influence appetite or food intake. This effect is independent of the amount of fat or plasma cholecystokinin changes.     

The effect of agar jelly on energy expenditure,appetite, gastric emptying and glycaemic response

Background and purpose

Agar contains a high amount of soluble fibre and has been shown to delay gastric emptying (GE) without impacting on glycaemic response (GR). The current study aimed to further the limited data on the effect of agar on metabolism by assessing the effects on GE and GR as well as appetite- and diet-induced thermogenesis (DIT).

Methods

In this randomized control trial, eleven healthy volunteers were tested on two occasions following an overnight fast. Following baseline and resting measurements, volunteers were either fed a fruit-flavoured drink (liquid) or consumed a fruit-flavoured jelly (jelly). The two were exactly the same in composition except the jelly contained 4 g of agar crystals. Both contained 50 g of available carbohydrate. DIT was measured using indirect calorimetry, GE using the ¹³C sodium acetate breath test, appetite using visual analogue scale and GR using finger prick blood samples.

Results

The jelly significantly delayed GE across all time points—latency phase (p = 0.07), lag phase (p = 0.04), half-time (p < 0.0001), ascension time (p = 0.025). The jelly also increased all appetite parameters—hunger (p = 0.006), fullness (p = 0.035), desire to eat (p = 0.03) and prospective consumption (p = 0.011). However, there were no significant differences in either GR or postprandial DIT between the liquid and jelly.

Conclusion

Agar delays GE and increases appetite but does not change GR or DIT most probably due to the increase in viscosity caused by the agar jelly.     

The effect of the macronutrient composition of breakfast on satiety and cognitive function in undergraduate students

Purpose

It is believed that breakfast is an important meal due to its effect on appetite control and cognitive performance, yet little evidence exists to support this hypothesis.

Methods

Using a crossover design, 33 healthy undergraduates (aged 22 ± 2 years with a BMI of 23.5 ± 1.7 kg/m²) were randomized one of four breakfast treatments: no breakfast, a low-protein breakfast containing no animal protein, a high-carbohydrate/low-protein breakfast containing animal protein or a low-carbohydrate/high-protein breakfast. After an overnight fast, participants reported to the laboratory and baseline appetite questionnaires and cognitive tests were completed. A baseline blood sample was also collected. These measures were repeated at regular intervals throughout the test session. An ad libitum lunch meal was provided 240 min after breakfast, and the amount eaten recorded. Diet diaries and hourly appetite questionnaires were completed for the rest of the day.

Results

The no-breakfast treatment had a marked effect on appetite before lunch (p < .05). Moreover, participants consumed more energy at lunch following the no-breakfast treatment (p < .05). There was no difference in appetite before lunch or food intake at lunch following any treatment when breakfast was eaten. However, food intake over the entire test day was lowest for the no-breakfast treatment (p < .05). Plasma glucose and insulin were lower following the high-protein/low-carbohydrate treatment compared to the low-protein/high-carbohydrate—no animal protein treatment (p < .05). Participants were less happy when they missed breakfast (p < .05), but there were no other statistically significant effects of breakfast on mood or cognitive performance.

Conclusions

These results suggest that changing the macronutrient content of breakfast influences the glycemic response, but has no effect on the appetitive or cognitive performance measures used in this present study.

     

The influence of the glycaemic index of breakfast and lunch on substrate utilisation during the postprandial periods and subsequent exercise

The present study investigated the effects of mixed high-carbohydrate (CHO) meals (breakfast and lunch) with different glycaemic indices (GI) on substrate metabolism during rest throughout the postprandial periods and during subsequent exercise. Nine recreationally active males completed two trials, high glycaemic index (HGI) and low glycaemic index (LGI), separated by 7 d in a randomised crossover design. In each trial, participants consumed breakfast and lunch, both of which were followed by a 3 h resting postprandial period. Following this, participants completed a 60 min run at 70 % of V O2max. The plasma glucose and serum insulin concentrations following both meals were significantly higher in the HGI trial than in the LGI trial (P<0.05). Serum insulin concentrations remained higher throughout the postprandial period following lunch in the HGI trial compared with the LGI trial (P<0.05). The total amount of fat oxidised was higher during the 3 h rest following lunch in the LGI trial than in the HGI trial (P<0.01) and subsequently CHO oxidation was lower (P<0.005). No significant differences in substrate utilisation were observed throughout the subsequent run. At 45 and 60 min, plasma glucose concentrations were higher in the LGI trial v. the HGI trial (P<0.05). The results of the present study provide further support that the GI concept can be successfully applied to mixed meals. The results also suggest that meals composed of LGI CHO may be more beneficial for maintaining a favourable metabolic milieu during the postprandial periods. Furthermore, during subsequent exercise, plasma glucose concentrations were better maintained following the LGI CHO meals.     

Percutaneous endoscopic gastrostomy (PEG) tube feeding of nursing home residents is not associated with improved body composition parameters

Objectives

To study differences in nutritional status and body composition, by feeding modality, among disabled nursing home residents.

Design

A retrospective chart-review study.

Setting

A nursing wing of a public urban geriatric center.

Participants

Three groups of patients: non-dysphagic, orally-fed dysphagic and percutaneous endoscopic gastrostomy -fed dysphagic patients. Intervention: Standard nursing care

Measurements

Basal metabolic rate, total energy expenditure and nitrogen balance under oral or percutaneous endoscopic gastrostomy feeding. Dietary intake was assessed during a 3-days period by daily-food intake protocols and a 24-hours urinary creatinine excretion to detect nitrogen balance and calculate body composition parameters.

Results

Data of 117 patients (55.5% females), mean age 84.6±7.5 (range 66–98 years) was analyzed. Dysphagic patients (60) differed from non-dysphagic patients (57) by lower body mass index (p=0.020), fat mass index (p=0.017), daily protein intake (p<0.0001), daily energy intake (p<0.001), protein related energy intake (p<0.001) and a negative nitrogen balance (p<0.001). In regression analyses, dysphagia was associated with increased risk of having a body mass index lower than 22.0kg/m2 (OR=2.60, 95% CI 1.135–5.943), a negative nitrogen balance (OR=2.33, 95% CI 1.063–4.669), a low fat mass index (OR=2.53, 95% CI 1.066–6.007), and low daily protein and energy intakes per body weight (OR=2.87, 95% CI 1.316–6.268 and OR=2.99, 95% CI 1.297–6.880). Compared with orally-fed dysphagic patients (21pts.), percutaneous endoscopic gastrostomy -fed patients (39pts.) received an additional mean energy intake of 30.5% kcal per day and mean protein intake of 26.0%. This additional intake was not associated with improved body composition parameters (such as fat free mass, skeletal mass or body mass index).

Conclusion

Dysphagic nursing home residents are characterized by worse nutritional, metabolic and body composition parameters, compared with non-dysphagic residents. Body composition parameters did not differ between orally-fed and percutaneous endoscopic gastrostomy-fed dysphagic patients, despite significantly better nutritional and metabolic parameters in PEG-fed patients. Other approaches (perhaps physical training, pharmacological etc.) should be sought to improve body composition of such patients.