The Effects of Orange Juice on Plasma Lipids
キーワード
概要
説明
Background:
Overweight and mild obesity are associated with insulin resistance and mild elevations in lipid risk factors which are not usually sufficiently abnormal to merit treatment. Such people are encouraged to lose weight to reduce their risk of progressing to type 2 diabetes and coronary heart disease, but there is clearly a potential role for dietary modifications to maximize any potential benefit of this weight loss. Flavonoids are known to have vascular effects which might enhance substrate delivery to metabolically active tissues, and thus improve insulin sensitivity. Moreover, there is much interest in the potentially beneficial effect of flavonoids on serum lipid profile.
There are many different dietary sources of flavonoids, with fruits such as apples, berries and citrus being rich sources. However, some researchers have expressed concern that a high dietary intake of 100% juice may contribute to the development of insulin resistance, obesity and the Metabolic Syndrome (Bazzano, Li et al. 2008), although this is not universally accepted (Fujioka, Greenway et al. 2006; O'Neil and Nicklas 2008). To date, there have been no studies investigating the effects of citrus fruits on indices of cardio-metabolic health in people who are presently healthy but are at risk of developing some features of the Metabolic Syndrome.
Aims:
To investigate the effects of orange juice (OJ) intake on appetite hormones, blood pressure and plasma lipids. In addition we aim to investigate any gene expression changes associated with OJ consumption, in particular in adipose tissue.
Experimental protocol and methods:
Overweight or obese men (BMI 27-35), who are otherwise healthy, will be recruited onto the study. They will attend the 'David Greenfield Human Physiology' laboratories on 5 convenient mornings, following an overnight fast. The 1st visit is a medical screening and will involve signing a consent form, completing medical screening, food frequency and activity questionnaires, having height, weight, and hip/waist circumference measurements taken and a sample of blood taken for CBC, urea, electrolytes, LFT, TFT, glucose and insulin analysis. Subjects will then be asked to complete a 3-day diet diary for macronutrient assessment. The 2nd visit will involve having a DEXA body composition scan, an adipose tissue biopsy and a blood sample taken for white blood cell harvest, serum lipids, glucose, insulin, cytokines, appetite hormones and catecholamine analysis. Starting on the following morning, subjects will then consume an orange drink (either OJ or a carbohydrate matched orange flavoured drink) once a day for 12 wks. A 3-day diet diary for macronutrient assessment will be recorded during wks 3,7and 11 of taking the drink, and measurements made at screening will be repeated on visits 3 and 4 which will take place in weeks 4 and 8. The final laboratory (5th) visit will be identical to visit 2.
日付
最終確認済み: | 02/28/2018 |
最初に提出された: | 05/08/2011 |
提出された推定登録数: | 05/08/2011 |
最初の投稿: | 05/09/2011 |
最終更新が送信されました: | 03/22/2018 |
最終更新日: | 03/26/2018 |
実際の研究開始日: | 04/30/2011 |
一次完了予定日: | 11/30/2012 |
研究完了予定日: | 01/31/2013 |
状態または病気
介入/治療
Dietary Supplement: Orange Juice
段階
アームグループ
腕 | 介入/治療 |
---|---|
Experimental: Orange Juice Juice high in flavonoids | |
Placebo Comparator: Orange Drink Sugars matched, low flavonoids orange drink |
適格基準
研究の対象となる年齢 | 40 Years に 40 Years |
研究に適格な性別 | Male |
健康なボランティアを受け入れる | はい |
基準 | Inclusion Criteria: - BMI 27-35 - waist circumference >96cm. - Serum Total Cholesterol >5mmol/l Exclusion Criteria: - Any clinically significant metabolic or endocrine abnormalities - screening blood results (other than lipids) outside of the normal range - fasting total cholesterol >7.0mmol/l - taking routine medication - herbal supplement use - food allergies or sensitivities related to the investigational product Regular citrus consumers (whole fruit or juice) daily consumption of sucrose or high fructose corn syrup containing soft-drinks |
結果
主な結果の測定
1. Total Serum Cholesterol concentration [after 3 months' intervention]
二次的な結果の測定
1. High Density Cholesterol (HDL) [after 3 months' intervention]
2. Low density cholesterol [after 3 months' intervention]
3. Gene expression in adipose tissue [after 3 months' intervention]
4. leptin [after 3 month intervention]
5. IL-1 [afetr 3 month intervention]
6. Blood Pressure [after 3months intervention]
7. Ghrelin [After 3 months intervention]
8. GLP-1 [After 3 months intervention]
9. insulin [After 3 months intervention]
10. IL-6 [After 3 months intervention]
11. TNF alpha [After 3 months intervention]