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BackgroundThe consumption of beetroot juice on a low nitrate diet may lower blood pressure (BP) and therefore reduce the risk of cardiovascular events. However, it is unknown if its inclusion as part of a normal diet has a similar effect on BP. The aim of the study was to conduct a randomized controlled trial with free-living adults to investigate if consuming beetroot juice in addition to a normal diet produces a measureable reduction in BP.MethodFifteen women and fifteen men participated in a double-blind, randomized, placebo-controlled, crossover study. Volunteers were randomized to receive 500 g of beetroot and apple juice (BJ) or a placebo juice (PL). Volunteers had BP measured at baseline and at least hourly for 24-h following juice consumption using an ambulatory blood pressure monitor (ABPM). Volunteers remained at the clinic for 1-h before resuming normal non-strenuous daily activities. The identical procedure was repeated 2-wk later with the drink (BJ or PL) not consumed on the first visit.ResultsOverall, there was a trend (P=0.064) to lower systolic blood pressure (SBP) at 6-h after drinking BJ relative to PL. Analysis in men only (n=13) after adjustment for baseline differences demonstrated a significant (P<0.05) reduction in SBP of 4 – 5 mmHg at 6-h after drinking BJ.ConclusionsBeetroot juice will lower BP in men when consumed as part of a normal diet in free-living healthy adults.Trial registrationanzctr.org.au ACTRN12612000445875

Ascorbic acid is one of the important water soluble vitamins. It is essential for collagen, carnitine and neurotransmitters biosynthesis. Most plants and animals synthesize ascorbic acid for their own requirement. However, apes and humans can not synthesize ascorbic acid due to lack of an enzyme gulonolactone oxidase. Hence, ascorbic acid has to be supplemented mainly through fruits, vegetables and tablets. The current US recommended daily allowance (RDA) for ascorbic acid ranges between 100-120 mg/per day for adults. Many health benefits have been attributed to ascorbic acid such as antioxidant, anti-atherogenic, anti-carcinogenic, immunomodulator and prevents cold etc. However, lately the health benefits of ascorbic acid has been the subject of debate and controversies viz., Danger of mega doses of ascorbic acid? Does ascorbic acid act as a antioxidant or pro-oxidant ? Does ascorbic acid cause cancer or may interfere with cancer therapy? However, the Panel on dietary antioxidants and related compounds stated that the in vivo data do not clearly show a relationship between excess ascorbic acid intake and kidney stone formation, pro-oxidant effects, excess iron absorption. A number of clinical and epidemiological studies on anti-carcinogenic effects of ascorbic acid in humans did not show any conclusive beneficial effects on various types of cancer except gastric cancer. Recently, a few derivatives of ascorbic acid were tested on cancer cells, among them ascorbic acid esters showed promising anticancer activity compared to ascorbic acid. Ascorbyl stearate was found to inhibit proliferation of human cancer cells by interfering with cell cycle progression, induced apoptosis by modulation of signal transduction pathways. However, more mechanistic and human in vivo studies are needed to understand and elucidate the molecular mechanism underlying the anti-carcinogenic property of ascorbic acid. Thus, though ascorbic acid was discovered in 17 th century, the exact role of this vitamin/nutraceutical in human biology and health is still a mystery in view of many beneficial claims and controversies. Historical perspectiveThe sea voyager/sailors developed a peculiar disease called scurvy when they were on sea. This was found to be due to eating non-perishable items and lack of fresh fruits and vegetables in their diet. A British naval Physician, Lind [1] documented that there was some substance in citrus fruits that can cure scurvy. He developed a method to concentrate and preserve citrus juice for use by sailors. British Navy was given a daily ration of lime or lemon juice to overcome ascorbic acid deficiency. Ascorbic acid was first isolated from natural sources and structurally character-

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Over the last years, evidence has accumulated suggesting that by systematically reducing the amount of dietary carbohydrates (CHOs) one could suppress, or at least delay, the emergence of cancer, and that proliferation of already existing tumor cells could be slowed down. This hypothesis is supported by the association between modern chronic diseases like the metabolic syndrome and the risk of developing or dying from cancer. CHOs or glucose, to which more complex carbohydrates are ultimately digested, can have direct and indirect effects on tumor cell proliferation: first, contrary to normal cells, most malignant cells depend on steady glucose availability in the blood for their energy and biomass generating demands and are not able to metabolize significant amounts of fatty acids or ketone bodies due to mitochondrial dysfunction. Second, high insulin and insulin-like growth factor (IGF)-1 levels resulting from chronic ingestion of CHO-rich Western diet meals, can directly promote tumor cell proliferation via the insulin/IGF1 signaling pathway. Third, ketone bodies that are elevated when insulin and blood glucose levels are low, have been found to negatively affect proliferation of different malignant cells in vitro or not to be usable by tumor cells for metabolic demands, and a multitude of mouse models have shown antitumorigenic properties of very low CHO ketogenic diets. In addition, many cancer patients exhibit an altered glucose metabolism characterized by insulin resistance and may profit from an increased protein and fat intake. In this review, we address the possible beneficial effects of low CHO diets on cancer prevention and treatment. Emphasis will be placed on the role of insulin and IGF1 signaling in tumorigenesis as well as altered dietary needs of cancer patients.

ObjectiveLarge preloads of protein and fat have been shown to lower glucose after a carbohydrate-rich meal in people with type 2 diabetes but add a considerable energy burden. Low calorie preloads [<5% of daily energy intake] have been tested in this study in people with prediabetes and with type 2 diabetes.Research design and methodsThis was an unblinded randomised crossover study with two placebo days and two active treatment days. Glucose was measured for 3 hours with fingerprick samples as well as continuous glucose monitoring [CGMS]. Twenty-four subjects with pre-diabetes or moderately controlled type 2 diabetes [fasting glucose < 10 and HbA1c < 8.5%] were recruited. The preload contained 17 g whey protein plus 3 g lactose and 5 g guar, and 1 g flavour material [including sucralose] dissolved in 150 ml cold water or 150 ml cold water with no additives. The breakfast test meal consisted of 2 slices of bread, margarine and jam [3 slices for men] with the test drink 15 minutes beforehand.ResultsPeak fingerprick glucose was reduced by 2.1 mmol/L at 45 min [p < 0.0001]. Average fingerprick glucose over 3 hours was reduced by 0.8 mmol/L [p = 0.0003]. There was no difference between those with diabetes or prediabetes or those on medication or not on medication.ConclusionsAn 80 kcal whey protein/fibre preload can lower average glucose over 3 hours by 0.8 mmol/L. If used long term before at least two carbohydrate-rich meals/day this preload could lower HbA1c by up to 1%.Trial registrationThe trial was registered with the Australian New Zealand Clinical Trials Registry number ACTRN12612001251819.

The dual digestibility assay accurately predicts the uptake of dietary nutrients (as grams of organic matter) in humans over the total tract. The assay is able to separately quantify the digestibility of nutrients in the upper and lower digestive tracts. The validation of the dual digestibility assay needs to be extended to a wider range of human diets.

BackgroundOffering the overweight or obese patient the option of choosing from a selection of weight loss diets has not been investigated in type 2 diabetes. The aim of the study was to investigate if the option to choose from, and interchange between a selection of diets (“Choice”), as opposed to being prescribed one set diet (“No Choice”), improves drop out rates and leads to improved weight loss and cardio-metabolic outcomes.MethodsThe study was a 12 month, randomized parallel intervention. A total of 144 volunteers with type 2 diabetes or pre-diabetes and a BMI >27 were randomized to “No Choice” or “Choice”. Those in the No Choice group were placed on a set weight loss diet (CSIRO) with no change permitted. Those in the Choice group could choose from, and interchange between, the CSIRO, South Beach or Mediterranean diets.ResultsThere were no differences in attrition rates or weight loss between the “Choice” and “No Choice”. In a secondary analysis of the intention-to-treat weight loss data with last measured weight carried forward gave a highly significant diet group by time by gender interaction (p = 0.002) with men doing better in the No Choice group overall (maximum difference “No Choice “-2.9 ± 4.6 kg vs. “Choice”-6.2 kg ± 5.3 kg at 6 months) and women doing better in the Choice group overall (maximum difference Choice -3.1 ± 3.7 kg vs. “No Choice” -2.0 kg ± 2.6 kg at 6 months).ConclusionsMen prefer direction in their weight loss advice and do less well with choice. A gender-specific approach is recommended when prescribing weight loss diets.Trial registrationanzctr.org.au ACTRN12612000310864.