Giulio Testolin

Polycyclic aromatic hydrocarbon contamination in the Italian diet

The content of total and carcinogenic polycyclic aromatic hydrocarbons (PAHs) in Italian foods was measured. The highest levels of PAHs were found in pizza baked in wood-burning ovens and barbecued beef and pork. Relatively high levels were also found in beet greens and squash, apples and bread, fried beef, pork and rabbit, cured meats and chocolate. Conversely low levels were detected in potatoes and cooked fish, beverages and eggs. The daily intake of total and carcinogenic PAHs also was calculated by multiplying the average consumption of each food by its mean concentration of PAHs. Cereal and milk products, meat, vegetables and fruits were the highest contributors to total PAH intake, since these products are the most important dietary components in Italy. The calculated total dietary PAH intake was 3 micrograms/day per person. The calculated intake of carcinogenic PAHs was 1.4 microgram/day per person. The dietary intake of PAHs was high compared with the calculated respiratory intake (370 ng/day) owing to polluted city air in Italy. These results confirm that food is the major source of human exposure to PAHs, due in particular to the high consumption of contaminated cereal products.

Absorption of lycopene from single or daily portions of raw and processed tomato

To study the relationship between lycopene intake and plasma concentration, ten healthy female subjects were given one or more portions of tomato purée or fresh raw tomato containing 16.5 mg total lycopene (all-trans + cis forms). In Expt 1 subjects (n 9) were randomly assigned the single portions of the two tomato products and blood samples were collected to follow the change in plasma carotenoid concentrations within the first 12 h and on each of the following 5 d (104 h). In Expt 2 subjects (n 10) were divided into two groups of five each receiving daily dietary portions of tomato purée or fresh raw tomato containing 16.5 mg total lycopene for 7 d. Fasting blood samples were collected daily. In Expt 1 the plasma total lycopene (all-trans + cis forms) concentration, after the single portions of tomato purée and raw tomato, varied significantly over time, with a first peak reached after 6 h, a further increase after 12 h and a slow decrease until 104 h. In Expt 2, when the tomato products were given daily, there was a day-by-day increase in the plasma total lycopene concentration, and through the following week of a diet without tomato there was a gradual decrease. However, values did not return to basal concentrations. Plasma total lycopene concentration was higher after the tomato purée intake than after the raw tomato in both the first (F(1,8) 7.597; P < 0.025) and the second experiments (F(1,8) 12.193; P < 0.01) demonstrating a significant effect of food matrix on absorption.

The validity of predicted body fat percentage from body mass index and from impedance in samples of five European populations

Objectives: To test and compare the validity of a body mass index (BMI)-based prediction equation and an impedance-based prediction equation for body fat percentage among various European population groups.Design: Cross-sectional observational study.Settings: The study was performed in five different European centres: Maastricht and Wageningen (The Netherlands), Milan and Rome (Italy) and Tampere (Finland), where body composition studies are routinely performed.Subjects: A total of 234 females and 182 males, aged 18–70 y, BMI 17.0–41.9 kg/m2.Methods: The reference method for body fat percentage (BF%REF) was either dual-energy X-ray absorptiometry (DXA) or densitometry (underwater weighing). Body fat percentage (BF%) was also predicted from BMI, age and sex (BF%BMI) or with a hand-held impedance analyser that uses in addition to arm impedance weight, height, age and sex as predictors (BF%IMP).Results: The overall mean (±s.e.) bias (measured minus predicted) for BF%BMI was 0.2±0.3 (NS) and−0.7±0.3 (NS) in females and males, respectively. The bias of BF%IMP was 0.2±0.2 (NS) and 1.0±0.4 (P<0.01) for females and males, respectively. There were significant differences in biases among the centres. The biases were correlated with level of BF% and with age. After correction for differences in age and BF% between the centres the bias of BF%BMI was not significantly different from zero in each centre and was not different among the centres anymore. The bias of BF%IMP decreased after correction and was significant from zero and significant from the other centres only in males from Tampere. Generally, individual biases can be high, leading to a considerably misclassification of obesity. The individual misclassification was generally higher with the BMI-based prediction.Conclusions: The prediction formulas give generally good estimates of BF% on a group level in the five population samples, except for the males from Tampere. More comparative studies should be conducted to get better insight in the generalisation of prediction methods and formulas. Individual results and classifications have to be interpreted with caution.European Journal of Clinical Nutrition (2001) 55, 973–979

The influence of thermic effect of food on satiety.

Objectives: To evaluate energy expenditure after three isoenergetic meals of different nutrient composition and to establish the relationship between the thermic effect of food (TEF), subsequent energy intake from a test meal and satiety sensations related to consumption.Design: The study employed a repeated measures design. Ten subjects received, in a randomized order, three meals of 2331±36 kJ (557±9 kcal). About 68% of energy from protein in the high protein meal (HP), 69% from carbohydrate in the high carbohydrate meal (HC) and 70% from fat in the high fat meal (HF).Setting: The experiments were performed at the University of Milan.Subjects: Ten normal body-weight healthy women.Methods: Energy expenditure was measured by indirect calorimetric measurements, using an open-circuit ventilated-hood system; intake was assessed 7 h later by weighing the food consumed from a test meal and satiety sensations were rated by means of a satiety rating questionnaire.Results: TEF was 261±59, 92±67 and 97±71 kJ over 7 h after the HP, HC and HF meals, respectively. The HP meal was the most thermogenic (P<0.001) and it determined the highest sensation of fullness (P=0.002). There were no differences in the sensations and thermic effect between fat and carbohydrate meals. A significant relationship linked TEF to fullness sensation (r=0.41, P=0.025). Energy intake from the test meal was comparable after HP, HC and HF meals.Conclusions: Our results suggest that TEF contributes to the satiating power of foods.Sponsorship: This work was supported by the National Research Council, targeted project ‘Prevention and Control of Disease Factors’, subproject ‘Nutrition’, grant no. 94.00365.PF41.

Weight, Protein, Fat, and Timing of Preloads Affect Food Intake

Two foods, one rich in protein (HP) and one rich in fat (HF), were employed to evaluate the effect of macronutrients on food intake and to underline the differences that occurred when the foods were served as uniform meal, as first course of a varied meal, and as a snack 2 h before a varied meal. Our results showed that HP food always exerted a higher effect on both intrameal satiation and postingestive satiety than HF food. When a uniform meal was consumed, satiation for the specific food was reached before fullness; in this condition, sensory characteristics of foods played an important role in controlling food intake and made the uniform meal more satiating than the varied one. The consumption of a snack far from a meal did not contribute to satiety; consequently, gastric filling seems to be an important factor determining the amount consumed in a varied meal.

Lycopene and vitamin C concentrations increase in plasma and lymphocytes after tomato intake. Effects on cellular antioxidant protection

Objective: This study seeks to verify whether the regular consumption of small amounts of tomato products can protect lymphocyte DNA and lipids from oxidative damage.Design: Standardized dietary intervention.Subjects: Twelve healthy female subjects (mean age 25.2 y).Intervention: Subjects were instructed to follow a standardized diet for 1 week, followed by 3 weeks consumption of the same diet enriched with small amounts of different tomato products providing as a mean 8 mg lycopene, 0.5 mg β-carotene and 11 mg vitamin C per day. Plasma and lymphocyte concentrations of carotenoids, vitamin C and vitamin E were analysed. Ex vivo protection of lymphocyte DNA from oxidative injury produced by iron ions was evaluated by means of the Comet assay, and lipid peroxidation by HPLC analysis of malondialdehyde (MDA).Results: Dietary intervention with tomato products increased lycopene concentration both in plasma (P<0.001) and lymphocytes (P<0.01). Vitamin C concentrations increased by ∼35% in plasma (P<0.05) and by ∼230% in lymphocytes (P<0.005). Vitamin E decreased significantly in plasma (P<0.0001) but not in lymphocytes. Finally, there was an improved protection from DNA oxidative damage (P<0.05) with no significant effect on MDA levels.Conclusions: Our results suggest that tomato products are not only good sources of lycopene but also sources of bioavailable vitamin C. A Regular intake of small amounts of tomato products can increase cell protection from DNA damage induced by oxidant species. This effect may originate from the synergism of different antioxidants present in tomatoes.Sponsorship: Supported by the Ministry of University and Scientific Research (MURST).

Post-Prandial Responses to Cereal Products Enriched with Barley β-Glucan

Background: High amounts of soluble β-glucan in barley products may exert beneficial effects on glucose tolerance and blood lipids. Objective: To investigate the acute postprandial response on plasma glucose, insulin and lipids after consumption of two experimental products made from barley flour enriched with β-glucan in comparison with similar products made from whole-wheat flour. Methods: A group of 10 healthy volunteers (5 males, age 25.4 ± 0.5 y, BMI 22.6 ± 0.7 Kg/m2) received at breakfast, in random order and in different days, portions (40g of available carbohydrate) of different cereal products or white bread consumed together with a load of 90000 UI retinol. Products were crackers and cookies made either from barley or whole-wheat flour in a 2 × 2 design, where the two factors were the cereal source of dietary fiber (DF), and the food processing. Barley products supplied 12 g DF, 50% soluble, with 3.5 g of β-glucan per portion. Whole-wheat products supplied about 14 g of dietary fiber, mainly in the insoluble form, with negligible amount of β-glucan. Fasting and post-prandial glucose and insulin were evaluated for 180 min after the meals; retinyl-palmitate (RP) and triacylglycerol (TAG) were evaluated hourly over 8 hours. Glycemic (GI) and Insulinemic (II) indexes of products were also assessed, using white bread as reference. Results: Glucose curves were significantly different between types of food processing (p < 0.01) but not between cereal sources of DF (p = 0.07). On the contrary, the effect of fiber but not of processing was evident when glucose response was expressed as Glycemic Index (effect of DF p < 0.01, effect of processing p = 0.69). Individual GI values were 78, 81, 49 and 34 for whole-wheat crackers (WWCr), whole-wheat cookies (WWc), barley crackers (BCr) and barley cookies (Bc) respectively. Insulin curves were significantly different both between type of processing and fiber source (p < 0.001 for both effects). Again, insulin indices were different between fiber but not between processing (p < 0.5 and p = 0.174 respectively). RP and TAG daily profiles were not significantly different between the factors studied. Conclusions: Products prepared from barley flour enriched with β-glucan exhibit favourable responses on glucose metabolism, and particularly on insulinemic responses. In general, cookies responded better to the addition of barley fiber than crackers. Our results highlight the complexity of the effect that barley fiber may exert when added to different food products in reducing postprandial metabolic responses.

Body composition assessment in spinal cord injury subjects.

Abstract.Total and segmental body composition (fat mass, FM; fat-free mass, FFM; bone mineral density, BMD) were evaluated in 13 sedentary spinal cord injury (SCI) subjects and in 13 able-bodied healthy males (control, C) using dual X-ray absorptiometry (DXA) and skinfold methods. In the SCI group, total FM was significantly higher (31.1±8.2 vs. 20.8±6.9%) and total FFM was significantly lower (62.2±8.9 vs. 73.5±6.4%) than in C subjects. Total BMD did not differ between the SCI and C groups (1.20±0.11 vs. 1.30±0.11 g/cm2). In the SCI group, segmental FM was higher in the legs and trunk, whereas BMD was lower in legs only. The skinfold method significantly underestimated FM in the SCI group. Body composition is severely modified in paralyzed segments. The predictive equations developed for healthy populations appear to be inapplicable to SCI subjects.

Effect of the ratio of casein phosphopeptides to calcium (w/w) on passive calcium transport in the distal small intestine of rats ☆

OBJECTIVE We investigated the influence of different ratios between casein phosphopeptides and calcium (CPP/Ca) in intestinal lumen on passive Ca transport across the distal small intestine of rats in vitro. METHODS We measured the amounts of passive Ca absorbed across the everted distal small intestine of rats with the use of radioactive 45Ca as tracer. Four CPP/Ca ratios (5, 10, 15, and 20 w/w) and three mineral concentrations (4, 8, and 12 mmol/L) were tested on groups of six rats. RESULTS We found a significant effect of the CPP/Ca ratio on mineral absorption (P < 0.001). The amounts of Ca absorbed increased from a ratio of 5 to a ratio of 15 and decreased with a ratio of 20, with a similar trend for every concentration tested. The more evident effect was found with the concentration of 12 mmol/L of Ca (P < 0.001 to 0.05). CONCLUSION The positive effect of CPPs on passive Ca absorption seems to depend on the relative amounts of both species in intestinal lumen. In this study, the ratio 15 was identified as the most efficient at increasing mineral transport. This evidence might be considered before suggesting CPP as a Ca dietary integrator, although more studies in vitro and in vivo are needed.

Evaluation of nutritional status in children with refractory epilepsy

Backgroundchildren affected by refractory epilepsy could be at risk of malnutrition because of feeding difficulties (anorexia, chewing, swallowing difficulties or vomiting) and chronic use of anticonvulsants, which may affect food intake and energy metabolism. Moreover, their energy requirement may be changed as their disabilities would impede normal daily activities. The aim of the present study was to evaluate nutritional status, energy metabolism and food intake in children with refractory epilepsy.Methods17 children with refractory epilepsy (13 boys and 4 girls; mean age 9 ± 3,2 years; Body Mass Index 15,7 ± 3,6) underwent an anthropometric assessment, body composition evaluation by dual-energy X-ray absorptiometry, detailed dietetic survey and measurement of resting energy expenditure by indirect calorimetry. Weight-for-age, height-for-age (stunting) and weight-for-height (wasting) were estimated compared to those of a reference population of the same age.Results40% of children were malnourished and 24% were wasted. The nutritional status was worse in the more disabled children. Dietary intake resulted unbalanced (18%, 39%, 43% of total daily energy intake derived respectively from protein, lipid and carbohydrate). Adequacy index [nutrient daily intake/recommended allowance (RDA) × 100] was < 60% for calcium iron and zinc.Conclusionmany children with refractory epilepsy would benefit from individual nutritional assessment and management as part of their overall care.