Reduced LDL particle size in children consuming a very-low-fat diet is related to parental LDL-subclass patterns

BACKGROUND: A genetically influenced atherogenic lipoprotein phenotype characterized by a predominance of small, dense LDL particles (subclass pattern B) can be induced by low-fat diets in healthy subjects with large LDL particles (pattern A). OBJECTIVE: The aim of this study was to test whether genetic predisposition to subclass pattern B contributes to susceptibility to induction of this trait by a low-fat diet. DESIGN: The prevalence of pattern B in children is relatively low compared with that in older individuals, but genetic susceptibility to this trait in offspring can be inferred by its presence in their parents. Plasma lipoproteins were analyzed 10 d after a change from a usual diet to a very-low-fat (10% fat), high-carbohydrate diet in offspring (mean age: 14 y; range: 7-28 y) of 22 families according to parental LDL-subclass patterns when consuming a low-fat diet: AxA mating (9 families with 19 children), AxB mating (5 families with 10 children), and BxB mating (8 families with 21 children). RESULTS: The very-low-fat, high-carbohydrate diet produced significantly greater decreases in LDL particle size in offspring of BxB parents (f1.gif" BORDER="0"> +/- SE: -0.55 +/- 0.16 nm) and AxB parents (-0.48 +/- 0.19 nm) than in offspring of AxA parents (0.14 +/- 0.20 nm). The number of children expressing pattern B with the 10%-fat diet and the proportion of children converting from pattern A to pattern B was significantly greater in offspring of BxB parents than in those with 1 or 2 pattern A parents. CONCLUSION: A very-low-fat, high-carbohydrate diet can induce expression of LDL-subclass pattern B in genetically predisposed children with low expression of the trait while consuming their usual diets.     

Higher levels of serum triglyceride and dietary carbohydrate intake are associated with smaller LDL particle size in healthy Korean women

The aim of this study was to investigate the influencing factors that characterize low density lipoprotein (LDL) phenotype and the levels of LDL particle size in healthy Korean women. In 57 healthy Korean women (mean age, 57.4 ± 13.1 yrs), anthropometric and biochemical parameters such as lipid profiles and LDL particle size were measured. Dietary intake was estimated by a developed semi-quantitative food frequency questionnaire. The study subjects were divided into two groups: LDL phenotype A (mean size: 269.7Å, n = 44) and LDL phenotype B (mean size: 248.2Å, n = 13). Basic characteristics were not significantly different between the two groups. The phenotype B group had a higher body mass index, higher serum levels of triglyceride, total-cholesterol, LDL-cholesterol, apolipoprotein (apo)B, and apoCIII but lower levels of high density lipoprotein (HDL)-cholesterol and LDL particle size than those of the phenotype A group. LDL particle size was negatively correlated with serum levels of triglyceride (r = -0.732, P < 0.001), total-cholesterol, apoB, and apoCIII, as well as carbohydrate intake (%En) and positively correlated with serum levels of HDL-cholesterol and ApoA1 and fat intake (%En). A stepwise multiple linear regression analysis revealed that carbohydrate intake (%En) and serum triglyceride levels were the primary factors influencing LDL particle size (P < 0.001, R² = 0.577). This result confirmed that LDL particle size was closely correlated with circulating triglycerides and demonstrated that particle size is significantly associated with dietary carbohydrate in Korean women.     

The small dense LDL particle/large buoyant LDL particle ratio is associated with glucose metabolic status in pregnancy

Background

The lipoprotein subfraction particle profile can be used to improve clinical assessments of cardiovascular disease risk and contribute to early detection of atherogenic dyslipidemia. Lipid alterations in gestational diabetes have been extensively studied, but the results have been inconsistent. Here, we investigated serum lipoprotein subfraction particle levels and their association with glucose metabolic status in pregnancy.

Methods

Twenty-eight pregnant women with gestational diabetes and 56 pregnant women with normal glucose tolerance matched for body mass index were enrolled in this study. We assessed fasting serum lipid concentrations and lipoprotein subfraction particle levels in participants between 24 and 28 weeks of gestation.

Results

The level of low-density lipoprotein (LDL) cholesterol was significantly lower in women with gestational diabetes than in those with normal glucose tolerance, but the triglyceride and high-density lipoprotein (HDL) cholesterol levels of the two groups were similar. Lipoprotein particle analysis showed that very-low-density lipoprotein (VLDL) particle number and the small dense LDL particle/large buoyant LDL particle (sdLDL-P/lbLDL-P) ratio were significantly higher in women with gestational diabetes than in those with normal glucose tolerance (P?=?0.013 and P?=?0.015, respectively). In multivariate analysis, fasting glucose was independently and positively associated with sdLDL-P/lbLDL-P ratio even after adjustment for maternal age, gestational weight gain, BMI and LDL cholesterol (standardized Beta?=?0.214, P?=?0.029).

Conclusions

The sdLDL-P/lbLDL-P ratio is higher in GDM compared with non-diabetic pregnant women, and positively and independently associated with fasting glucose in pregnant women.

     

LDL particle size, fat distribution and insulin resistance in obese children

BACKGROUND: The importance of small dense low-density lipoprotein (sdLDL) cholesterol in coronary heart disease has been demonstrated in many studies. Body fat accumulation, especially abdominal adiposity, is one of the important factors modifying the expression of sdLDL in adults. OBJECTIVE: To determine the prevalence of sdLDL in obese children, and to investigate its relationship with anthropometric and metabolic variables. SUBJECTS: A total of 30 obese children (22 males, 8 females) aged 12.6+/-0.6 years (mean+/-s.e.), who presented to our outpatient clinic with obesity. METHODS: LDL peak particle diameter was determined using gel electrophoresis. LDL subclasses were classified into sdLDL (pattern B; diameter<25.5 nm) and non-sdLDL (pattern A; diameter>or=25.5 nm). Anthropometric and metabolic variables were also determined to identify factors modifying LDL particle size. RESULTS: sdLDL was detected in 11 children (40.0%). In children with sdLDL, waist/height ratio was significantly higher (P=0.0466), and they had significantly higher triglyceride (TG) (P=0.0035) and lower high-density lipoprotein cholesterol (HDLC) levels (P=0.036). Peak LDL diameter as a continuous variable was significantly correlated with HDLC and TG levels. In multiple regression analysis, body mass index and waist/height ratio were significant determinants of the peak LDL diameter variability. CONCLUSIONS: We found a high prevalence of sdLDL in obese children, and a relationship of peak LDL diameter with abdominal fat accumulation, HDLC and TG levels. The presence of sdLDL might be an important risk factor for the metabolic syndrome.     

Excessive iodine intake in schoolchildren

Purpose

Inadequate iodine intake may result in iodine deficiency disorders (IDD). Thus, for more than 50?years, policies for the regulation of salt fortification with iodine have existed in Brazil. In 2003, a study on 6–14-year-old schoolchildren from regions of the state of S?o Paulo showed a median urinary iodine concentration of 360?μg/L. The objective of the present study was to assess the iodine nutrition status among schoolchildren.

Methods

The study was conducted on 828 schoolchildren aged 4–13?years from eight schools in the interior of the state of S?o Paulo. A casual urine sample was collected from each volunteer for iodine determination by the adapted method of Sandell-Kalthoff.

Results

Only 1.9% (n?=?16) of the children evaluated had low values of urinary iodine (<100?μg/L), while 24.6% had urinary iodine excretion values between 200 and 300?μg/L, and 67.1% had values above >300?μg/L.

Conclusions

The results show that the iodine nutritional status of the schoolchildren studied is characterized by a high urinary iodine excretion, which might reveal an increase in iodine consumption by this population.     

Effect of different forms of dietary hydrogenated fats on LDL particle size

BACKGROUND: Dietary trans fatty acids (FAs), which are formed during the process of hydrogenating vegetable oil, are known to increase plasma LDL-cholesterol concentrations. However, their effect on LDL particle size has yet to be investigated. OBJECTIVE: We investigated the effect of trans FA consumption on the electrophoretic characteristics of LDL particles. DESIGN: Eighteen women and 18 men each consumed 5 experimental diets in random order for 35-d periods. Fat represented 30% of total energy intake in each diet, with two-thirds of the fat in the form of semiliquid margarine (0.6 g trans FAs/100 g fat), soft margarine (9.4 g trans FAs/100 g fat), shortening (13.6 g trans FAs/100 g fat), stick margarine (26.1 g trans FAs/100 g fat), or butter, which was low in trans FAs (2.6 g trans FAs/100 g fat) but rich in saturated fat. LDL particle size and distribution were characterized by nondenaturing, 2-16% polyacrylamide gradient gel electrophoresis. RESULTS: Relative to the LDL particle size observed after consumption of the butter-enriched diet, LDL particle size decreased significantly and in a dose-dependent fashion with increasing amounts of dietary trans FAs (P < 0.001). Cholesterol concentrations in large (> 260 A) and medium-sized (255-260 A) LDL particles also increased proportionately to the amount of trans FAs in the diet. CONCLUSION: Consumption of dietary trans FAs is associated with a deleterious increase in small, dense LDL, which further reinforces the importance of promoting diets low in trans FAs to favorably affect the lipoprotein profile.     

Milk-derived fatty acids are associated with a more favorable LDL particle size distribution in healthy men

A predominance of small dense LDL (sdLDL) particles is a well-established component of the atherogenic lipoprotein phenotype associated with insulin resistance and increased risk for coronary heart disease. However, the influence of diet on LDL particle size distribution is not clear. We investigated (cross-sectionally) the relations between LDL profile and dietary fatty acids (FAs) in 291 healthy men (62-64 y old) with a range of insulin sensitivities. Individuals completed a 7-d dietary record, and fasting plasma insulin, lipid, and lipoprotein concentrations as well as serum and adipose tissue FA composition were determined. The LDL profile was examined by polyacrylamide gradient gel electrophoresis, protein-staining, and quantitative scanning, giving LDL peak particle size and the percentage distribution of LDL in 4 subfractions. The men were divided into tertiles of percentage distribution of sdLDL. Small dense LDL was positively related to plasma triacylglycerol and fasting insulin concentrations (both P < 0.0001) and inversely related to HDL cholesterol (P < 0.0001). No strong relations were found between sdLDL and the reported intake of SFA, monounsaturated fatty acids, or PUFA. However, individual FAs typically found in milk products were associated with a more favorable LDL profile (i.e., fewer sdLDL particles). This was shown for 4:0-10:0 and 14:0 in the diet (both P < 0.05), 15:0 and 17:0 in serum phospholipids (both P < 0.05), and 15:0 in serum nonesterified FAs (P < 0.01). Furthermore, 20:3(n-6) in adipose tissue and serum phospholipids was positively related to sdLDL. Therefore, LDL particle size distribution appears to be modified by dietary factors with an apparently beneficial effect of milk products.     

Measuring the prevalence of overweight in Texas schoolchildren

OBJECTIVES: We describe results from year 1 of a surveillance system to monitor body mass index in children at the state level. METHODS: A sample of 6630 children attending Texas public schools, weighted to represent 4th, 8th, and 11th grades within race/ethnic subpopulations, was assessed. Body mass index was calculated from measured height and weight; demographic information was obtained from a questionnaire. RESULTS: Prevalence of overweight was 22.4%, 19.2%, and 15.5% for 4th-, 8th-, and 11th-grade students, respectively. Overweight prevalence was highest among Hispanic boys (29.5%-32.6%), fourth-grade Hispanic girls (26.7%), and fourth- and eighth-grade African American girls (30.8% and 23.1%, respectively). Eleventh-grade White/other girls had the lowest prevalence of overweight (5.5%). CONCLUSIONS: These data confirm the increasing prevalence of overweight among US children, especially among Hispanic and African American students compared to White/other students and fourth-grade students relative to 8th- and 11th-grade students.     

Portion size of food affects energy intake in normal-weight and overweight men and women

BACKGROUND: Large portions of food may contribute to excess energy intake and greater obesity. However, data on the effects of portion size on food intake in adults are limited. OBJECTIVES: We examined the effect of portion size on intake during a single meal. We also investigated whether the response to portion size depended on which person, the subject or the experimenter, determined the amount of food on the plate. DESIGN: Fifty-one men and women were served lunch 1 d/wk for 4 wk. Lunch included an entrée of macaroni and cheese consumed ad libitum. At each meal, subjects were presented with 1 of 4 portions of the entrée: 500, 625, 750, or 1000 g. One group of subjects received the portion on a plate, and a second group received it in a serving dish and took the amount they desired on their plates. RESULTS: Portion size significantly influenced energy intake at lunch (P < 0.0001). Subjects consumed 30% more energy (676 kJ) when offered the largest portion than when offered the smallest portion. The response to the variations in portion size was not influenced by who determined the amount of food on the plate or by subject characteristics such as sex, body mass index, or scores for dietary restraint or disinhibition. CONCLUSIONS: Larger portions led to greater energy intake regardless of serving method and subject characteristics. Portion size is a modifiable determinant of energy intake that should be addressed in connection with the prevention and treatment of obesity.     

Serum 25-hydroxyvitamin D is a predictor of serum 1,25-dihydroxyvitamin D in overweight and obese patients

Recent research suggests that 1,25-dihydroxyvitamin D [1,25(OH)(2)D], a steroid hormone that regulates calcium homeostasis, may also play a role in the development and progression of cancer, multiple sclerosis, cardiovascular, and other diseases. Decreased serum 1,25(OH)(2)D concentrations are often observed in overweight and obese patients. However, little is known about the factors that may influence 1,25(OH)(2)D renal synthesis, because it is generally accepted that serum 1,25(OH)(2)D concentration is strictly regulated by parathyroid hormone and serum concentrations of calcium and phosphorus. In this study, the associations among serum 1,25(OH)(2)D, serum 25-hydroxyvitamin D [25(OH)D], and body composition were analyzed in 1779 patients with excess body weight registered in a Metabolic and Medical Lifestyle Management Clinic in Oslo, Norway. According to our results, serum 25(OH)D, adiposity, age, season of blood sampling, and gender directly influence serum 1,25(OH)(2)D (r = 0.33; P < 0.001), with serum 25(OH)D being the strongest predictor for serum 1,25(OH)(2)D. The 1,25(OH)(2)D concentrations were 25.4 pmol/L (95% Cl: 19.3-31.5; P < 0.001) lower in the lowest 25(OH)D quartile to compared with highest quartile. A seasonal variation was observed for both vitamin D metabolites. Thus, our results suggest that in patients with excess body weight, serum 1,25(OH)(2)D concentrations were associated with 25(OH)D and varied during the year. Therefore, it may also be valuable to measure both serum 25(OH)D and 1,25(OH)(2)D for the evaluation of vitamin D status in overweight and obese persons.     

Comparison of a dietary portfolio diet of cholesterol-lowering foods and a statin on LDL particle size phenotype in hypercholesterolaemic participants

The effect of diet v. statins on LDL particle size as a risk factor for CVD has not been examined. We compared, in the same subjects, the impact of a dietary portfolio of cholesterol-lowering foods and a statin on LDL size electrophoretic characteristics. Thirty-four hyperlipidaemic subjects completed three 1-month treatments as outpatients in random order: a very-low saturated fat diet (control); the same diet with 20 mg lovastatin; a dietary portfolio high in plant sterols (1 g/4200 kJ), soya proteins (21.4 g/4200 kJ), soluble fibres (9.8 g/4200 kJ) and almonds (14 g/4200 kJ). LDL electrophoretic characteristics were measured by non-denaturing polyacrylamide gradient gel electrophoresis of fasting plasma at 0, 2 and 4 weeks of each treatment. The reductions in plasma LDL-cholesterol levels with the dietary portfolio and with statins were comparable and were largely attributable to reductions in the estimated concentration of cholesterol within the smallest subclass of LDL (portfolio - 0.69 (se 0.10) mmol/l, statin - 0.99 (se 0.10) mmol/l). These were significantly greater (P < 0.01) than changes observed after the control diet ( - 0.17 (se 0.08) mmol/l). Finally, baseline C-reactive protein levels were a significant predictor of the LDL size responsiveness to the dietary portfolio but not to the other treatments. The dietary portfolio, like the statin treatment, had only minor effects on several features of the LDL size phenotype, but the pronounced reduction in cholesterol levels within the small LDL fraction may provide additional cardiovascular benefit over the traditional low-fat diet of National Cholesterol Education Program Step II.     

ApoE polymorphism in a small Mediterranean island: relationships with plasma lipids,lipoproteins and LDL particle size

Polymorphisms of apoE gene are able to modulate lipoprotein metabolism at different steps and to influence LDL-cholesterol (LDL-C) levels and also other lipoproteins features. Population studies documented large differences in the frequency of apoE alleles which could be even related to the prevalence of cardiovascular disease. In this study we evaluated the apoE genotypes and allele frequency in 576 subjects living in a small island in the Tyrrhenian Sea and the relative contribution of apoE polymorphism on plasma lipid and lipoprotein profile, including LDL particle size. We found a cumulative frequency of 0.073, 0.866 and 0.061 for 2, 3 and 4 alleles respectively. Moreover 3 subjects had only triglyceride levels significantly lower and LDL-C and lipoprotein (a) (Lp(a)) levels higher than 2 carriers. LDL-particle size was significant smaller in 2 subjects than both 3 and 4 carriers, but the difference disappeared when data were adjusted for triglycerides. In conclusion we have provided further evidence of a low prevalence of 4 allele in a Mediterranean population which may represent a genetic protective factor of these populations. Environmental factors, such as diet, occurring in this area may have attenuated the influence of this gene on plasma lipoproteins.     

Algal docosahexaenoic acid affects plasma lipoprotein particle size distribution in overweight and obese adults

Fish oils containing both EPA and DHA have been shown to have beneficial cardiovascular effects, but less is known about the independent effects of DHA. This study was designed to examine the effects of DHA on plasma lipid and lipoprotein concentrations and other biomarkers of cardiovascular risk in the absence of weight loss. In this randomized, controlled, double-blind trial, 36 overweight or obese adults were treated with 2 g/d of algal DHA or placebo for 4.5 mo. Markers of cardiovascular risk were assessed before and after treatment. In the DHA-supplemented group, the decrease in mean VLDL particle size (P ≤ 0.001) and increases in mean LDL (P ≤ 0.001) and HDL (P ≤ 0.001) particle sizes were significantly greater than changes in the placebo group. DHA supplementation also increased the concentrations of large LDL (P ≤ 0.001) and large HDL particles (P = 0.001) and decreased the concentrations of small LDL (P = 0.009) and medium HDL particles (P = 0.001). As calculated using NMR-derived data, DHA supplementation reduced VLDL TG (P = 0.009) and total TG concentrations (P = 0.006). Plasma IL-10 increased with DHA supplementation to a greater extent than placebo (P = 0.021), but no other significant changes were observed in glucose metabolism, insulin sensitivity, blood pressure, or markers of inflammation with DHA. In summary, DHA supplementation resulted in potentially beneficial changes in some markers of cardiometabolic risk, whereas other markers were unchanged.     

Prevalence of overweight and obesity in schoolchildren in rural areas

Objectives

To estimate the prevalence of overweight and obesity in schoolchildren in rural areas.

Methods

A cross-sectional study was carried out in a sample of 1,513 schoolchildren aged 6, 11 and 14 years. Data were collected on height and weight with digital scales equipped with a measuring rod. We used three criteria to define overweight and obesity: Cole's points, the Centers for Disease Control and Prevention (CDC) criteria and Hernandez's tables.

Results

When Cole's points were used, 24.6% (95%CI: 22.5 - 26.8) were overweight and 11.6% (95%CI: 10-13.3) were obese; these percentages were higher in children aged 11 and 6 years, respectively. According CDC growth charts, 19.8% of children (95%CI: 17.9-21.9) were overweight and 16.5% (95%CI: 14.7-18.4) were obese, corresponding to higher percentages at 14 and 6 years. When Hernandez's tables were used, 11.5% (95%CI: 10-13.2) were overweight and 18.6% (95%CI: 16.7-20.6) were obese, and both disorders were higher in children aged 11 years. The risk of obesity and overweight was higher in small rural areas (<5,000 people), with OR = 1.49 (95%CI: 1.13-1.95) and OR = 1.33 (95%CI: 1.06-1.67), respectively.

Conclusions

The prevalence of overweight and obesity in schoolchildren in rural areas is very high and is even higher in towns with less than 5,000 inhabitants.     

Enrollment in English-as-a-second-language class as a predictor of tuberculosis infection in schoolchildren.

OBJECTIVE: To assess the rate of tuberculosis infection among Hispanic students enrolled in English-as-a-Second-Language classes compared with Hispanic and non-Hispanic students not enrolled in such classes. METHODS: Using Mantoux tuberculin skin tests, the authors screened 720 students--out of 844 eligible--in two schools with predominantly Hispanic populations. Ethnicity and enrollment in the English-as-a-Second Language classes were recorded for each student. The rate of skin test positivity was compared for students enrolled and not enrolled in these classes. RESULTS: The incidence of positive tests among Hispanic students enrolled in an English-as-a-Second-Language class was 10.6%, compared with 1.3% for Hispanic students not enrolled (relative risk 8.3, 95% confidence interval 2.92, 23.8). There was no statistically significant difference in incidence rates for non-Hispanic students (0.5%) and Hispanic students (1.3%) who were not enrolled in English-as-a-Second-Language class (relative risk 2.4, 95% confidence interval 0.27, 20.9). CONCLUSION: School-based tuberculin screening programs targeted at students enrolled in English-as-a-Second-Language classes can be effective and are not racially discriminatory.     

Improvements in LDL particle size and distribution by short-term alternate day modified fasting in obese adults

Alternate day modified fasting (ADMF) beneficially modulates several indicators of CHD risk, but its effects on LDL particle size have never been tested. Accordingly, we examined the effects of ADMF on LDL particle size and distribution in obese adults. Sixteen obese subjects participated in a 10-week trial with three consecutive phases: (1) 2-week control phase; (2) 4-week ADMF controlled feeding phase; (3) 4-week ADMF self-selected feeding phase. After 8 weeks of diet, body weight and waist circumference were reduced (P?相似文献   

Dietary sucrose intake is related to serum leptin concentration in overweight pregnant women

Background  

Overweight, characterized by low-degree systemic inflammation, predisposes women to impaired glucose metabolism during pregnancy. Adipokine leptin participates in the regulation of energy balance and immune action.     

深圳市中小学生超重与肥胖现况分析

目的了解广东省深圳市中小学生超重与肥胖现状, 为改善儿童青少年健康状况提供依据。方法采用分层整群随机抽样方法选取深圳市42所学校的65 305名学生为研究对象, 测量学生身高、体重, 通过计算体质指数(BMI)筛查不同区划、年龄、性别、学段学生的超重与肥胖检出率。结果深圳市中小学生超重、肥胖检出率分别为13.29%、9.03%, 其中男生分别为15.97%、11.58%, 女生分别为9.90%、5.80%;小学生、初中生、高中生超重检出率分别为14.26%、13.33%、11.34%, 肥胖检出率分别为12.27%、6.78%、4.85%, 小学生最高, 初中生次之, 高中生最低;深圳关内学生超重、肥胖检出率分别为14.19%、10.15%, 关外学生超重、肥胖检出率分别为12.34%、7.85%, 关内高于关外;以上差异均存在统计学意义(均P<0.01)。结论深圳市中小学生超重、肥胖问题不容忽视, 男生的超重与肥胖现象较为明显, 小学生的超重与肥胖问题较为突出。     

The ratio of animal protein intake to potassium intake is a predictor of bone resorption in space flight analogues and in ambulatory subjects

BACKGROUND: Bone loss is a critical concern for space travelers, and a dietary countermeasure would be of great benefit. Dietary protein and potassium-associated bicarbonate precursors may have opposing effects on the acid-base balance in the body and therefore on bone loss. OBJECTIVE: In 2 studies, we examined the ability of dietary protein and potassium to predict markers of bone metabolism. DESIGN: In the first study, 8 pairs of male identical twins were assigned to 1 of 2 groups: bed rest (sedentary, or SED, group) or bed rest with supine treadmill exercise in a lower-body negative pressure chamber (EX group). In a second study, groups of 4 subjects lived in a closed chamber for 60 or 91 d, and dietary data were collected for two or three 5-d sessions. Urinary calcium, N-telopeptide, and pyridinium cross-links were measured before bed rest; on bed rest days 5-6, 12-13, 19-20, and 26-27; and daily during the chamber studies. Data were analyzed by Pearson's correlation (P < 0.05). RESULTS: The ratio of animal protein intake to potassium intake was significantly correlated with N-telopeptide in the SED group during bed rest weeks 3 and 4 (r = 0.77 and 0.80) and during the 91-d chamber study (r = 0.75). The ratio of animal protein intake to potassium intake was positively correlated with pyridinium cross-links before bed rest in the EX group (r = 0.83), in the EX group during bed rest week 1 (r = 0.84), and in the SED group during bed rest week 2 (r = 0.72) but not during either chamber study. In both studies, these relations were not significant with the ratio of vegetable protein intake to potassium intake. CONCLUSIONS: The ratio of animal protein intake to potassium intake may affect bone in ambulatory and bed-rest subjects. Changing this ratio may help to prevent bone loss on Earth and during space flight.