Muscle-reducing obesity is the most common form of obesity in the elderly, so it is more difficult for the elderly to lose weight. The efficacy and safety of low-carbohydrate diet (LCD) for weight loss in the elderly remains controversial. This study aimed to explore the effect and safety of LCD on weight loss in overweight and obese elderly people.

Obese or overweight elderly (> 60 years old) with a BMI greater than 24 were recruited to use a restricted LCD for 1–3 months for weight loss intervention. According to the time, participants were divided into short-time group (< 30 days), medium-time group (< 31–60 days) and long-time group (> 60 days). The enrolled subjects were given an energy-restricted LCD for weight reduction intervention (1200–1400 kcal/d, carbohydrate accounts for 15–20% of energy). The primary outcome was change in body composition included weight, BMI, fat mass, and waist circumference, and there were other secondary outcomes including blood sugar, blood lipid and uric acid.

Thirty-two obese or overweight elderly completed a LCD for 1–3 months, mean age were 64.9 ± 4.2 years, median intervention time was 56 (range: 26,100); mean BMI was 29.62 ± 3.70kg/m2. After LCD intervention, the average body weight of the three groups decreased by 2.92 ± 0.77 kg, 5.57 ± 1.99 kg and 10.48 ± 2.63 kg; the average BMI decreased by 1.43 ± 0.34 kg/m, 2.18 ± 0.99 kg/m and 3.18 ± 1.77 kg/m; the average body fat decreased by 2.28 ± 0.43 kg, 4.07 ± 2.08 kg and 7.05 ± 2.53 kg; and the average muscle decreased by 0.68 ± 0.76 kg, 1.32 ± 0.78 kg and 2.45 ± 2.03 kg (P < 0.05). The average muscle loss was less than 20% of the total weight loss. Covariance analysis adjusted by sex and age showed that the percentage changes of body weight, BMI, body fat and waist circumference were significant different among the three groups (p < 0.05), which had linear trends with the intervention time, while the percentage of muscle and body fat decreased was not significantly different among the three groups, and did not increase with the intervening time (p > 0.05). Symptoms of patients with hypertension or sleep apnea syndrome were alleviated. There were no serious adverse events during weight loss.LCD with restricted energy is a safe and effective weight-loss intervention for overweight or obese elderly people. It can significantly reduce BMI and body fat without losing more muscle with the increase of weight loss time.

The associations between grains and carbohydrate intake and type 2 diabetes mellitus are controversial. This study aimed to evaluate the relationship between grains, carbohydrate intakes and the risk of type 2 diabetes mellitus in China.

This was a 1:2 (sex/age) matched case-control study, participants were adults. Cases were diabetics diagnosed within 3 months and the controls were without disorder of glucose metabolism. Face-to-face interviews were conducted to collect information on their socio-demographic characteristics, lifestyle factors, and dietary intakes using structured questionnaires. Grains were divided into whole, refined and common grain, and the carbohydrate intake was also calculated. The study participants were divided into quartiles (Q1 (lowest), Q2, Q3, and Q4) by food and nutrients intakes separately. Multivariable conditional logistic regression was used to explore the association of foods and nutrients with type 2 diabetes mellitus after adjusting for potential confounders. Trend test were performed by treating quartiles variables as continuous variables.

Our study enrolled 384 type 2 diabetes mellitus patients (males 162, females 222) and 768 controls (males 324, females 444). Multivariable conditional logistic regression analysis(Ver. 21.0; PSS Inc.,Chicago,IL,USA) showed that moderate amount intake of total cereals was inversely associated with type 2 diabetes mellitus. The adjusted OR of the second quartile (Q2, 223g/d) and the third quartile (Q3, 255g/d) were 0.60(95%CI:0.38–0.93) and 0.51(95%CI:0.33–0.79), respectively, compared with the lowest quartile (Q1, 165g/d), but this inverse association was not found in the highest quartile (Q4, 307g/d) and the OR was 0.74(95%CI:0.47–1.15). There was significant negative association between whole grains intake and type 2 diabetes mellitus with the OR of the highest intake 0.48(95%CI:0.31–0.77) compared with the lowest intake(Ptrend = 0.001).No association was found between refined grains intake intake and type 2 diabetes mellitus, and neither did common grain intake. Higher carbohydrate intake may have a beneficial effect on type 2 diabetes mellitus. The best effect was found in the second quartile intake (Q2, 264g/d), with an adjusted OR of 0.56 (95%CI:0.37–0.84) compared with the lowest quartile intake (Q1, 220g/d).The OR of Q3 (285g/d) and Q4 (334g/d) were 0.69 (95%CI:0.48–1.00) and 0.66 (95CI:0.44–1.00) respectively(Ptrend p = 0.017).

Moderate amount of total cereals intake may benefit to type 2 diabetes mellitus, however, much lower and higher intake can increase the risk. Higher intake of whole grains was associated with a lower risk of type 2 diabetes mellitus. Carbohydrate intake was negative associated with type 2 diabetes mellitus.

The estimation of dietary intake in population-based studies is often assessed by the FFQ. The objective of our study is to evaluate the validity of an FFQ used to assess dietary fatty acid intake among middle-aged Chinese adults in Southern China.

The method of triads was applied to obtain the validity coefficients (VC) of the FFQ for specific fatty acids. A subsample was randomly selected from an earlier cross-sectional study. The FFQ and 3d dietary records were used for dietary assessment, and the fatty acid composition of erythrocyte membranes was determined as the biomarker.

The Spearman correlation coefficients between the FFQ and 3d dietary records were moderate to good (r = 0·28–0·66). The VC of the FFQ estimated by the method of triads were 0·72, 0·61, 0·65, 0·75 and 0·67 for MUFA, total n-6 fatty acids, α-linolenic acid, EPA and DHA, respectively. The VC could not be calculated for SFA, PUFA and total n-3 fatty acids because of negative correlations among the three measurements. But, the correlations between the FFQ and the dietary records were moderate for these fatty acids.

Our FFQ applied in Southern Chinese adults was valid to estimate their dietary fatty acid intake and was thus suitable for use in a large cohort study.