miercuri, 16 iulie 2014
marți, 12 februarie 2013
miercuri, 15 februarie 2012
marți, 14 februarie 2012
marți, 1 noiembrie 2011
Is there a role for carbohydrate restriction in the treatment and prevention of cancer?
Is there a role for carbohydrate restriction in the treatment and prevention of cancer?
Rainer J Klement and Ulrike Kammerer
Nutrition & Metabolism 2011, 8:75 doi:10.1186/1743-7075-8-75
Published: 26 October 2011Abstract
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/IGF-1 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 anti-tumorigenic properties of very low-CHO ketogenic diets. In addition, many cancer patients exhibit an altered glucose metabolim 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 IGF-1 signaling in tumorigenesis as well as altered dietary needs of cancer patients.
luni, 10 octombrie 2011
Impact of caloric and dietary restriction regimens on markers of health and longevity in humans and animals: A summary of available findings
vineri, 23 septembrie 2011
marți, 26 iulie 2011
miercuri, 29 iunie 2011
luni, 27 iunie 2011
marți, 26 aprilie 2011
studiu nou despre post
The dietary recommendation for cancer patients receiving chemotherapy, as described by the American Cancer Society, is to increase calorie and protein intake. Yet, in simple organisms, mice, and humans, fasting-no calorie intake-induces a wide range of changes associated with cellular protection, which would be difficult to achieve even with a cocktail of potent drugs. In mammals, the protective effect of fasting is mediated, in part, by an over 50% reduction in glucose and insulin-like growth factor 1 (IGF-I) levels. Because proto-oncogenes function as key negative regulators of the protective changes induced by fasting, cells expressing oncogenes, and therefore the great majority of cancer cells, should not respond to the protective signals generated by fasting, promoting the differential protection (differential stress resistance) of normal and cancer cells. Preliminary reports indicate that fasting for up to 5 days followed by a normal diet, may also protect patients against chemotherapy without causing chronic weight loss. By contrast, the long-term 20 to 40% restriction in calorie intake (dietary restriction, DR), whose effects on cancer progression have been studied extensively for decades, requires weeks-months to be effective, causes much more modest changes in glucose and/or IGF-I levels, and promotes chronic weight loss in both rodents and humans. In this study, we review the basic as well as clinical studies on fasting, cellular protection and chemotherapy resistance, and compare them to those on DR and cancer treatment. Although additional pre-clinical and clinical studies are necessary, fasting has the potential to be translated into effective clinical interventions for the protection of patients and the improvement of therapeutic index.Oncogene advance online publication, 25 April 2011
luni, 11 aprilie 2011
1861 US ARMY dietary guidlines
A variety of foods are needed to avoid monotony and increase assimilation.
A healthy diet must conform to the physiological requirements of the season with less animal fats in the summer dietary, and more starch, vegetables, and fruits.
Fresh fruits are always preferable to dry or preserved ones.
Farinaceous vegetables are more nourishing than roots or grasses.
The best soldiers in the world are fed on dark colored bread.
French army dietaries provide nutritious soups made with meat or vegetables.
The woody fibre of the vegetable provides bulk as well as nourishment.
Each company should have at least one educated cook.
Beans, unless thoroughly cooked, are only fit for horses. When half-cooked, they will provoke indigestion and diarrhea.
Ardent spirits are not necessary for health and the soldier is better off without them.
Soldiers must be well fed to bear the fatigues of marching, to encounter unaffected the changes of climate, and to develop a high muscular tone.
luni, 4 aprilie 2011
luni, 21 martie 2011
vineri, 18 martie 2011
postul religios e sanatos
Richard J Bloomer, Mohammad M Kabir, John F Trepanowski, Robert E Canale and Tyler M Farney
For all author emails, please log on.
Nutrition & Metabolism 2011, 8:17 doi:10.1186/1743-7075-8-17
Published: 18 March 2011
Abstract (provisional)
Background
Dietary modification via both caloric and nutrient restriction is associated with multiple health benefits, some of which are related to an improvement in antioxidant status and a decrease in the production of reactive oxygen species. The Daniel Fast is based on the Biblical book of Daniel, is commonly partaken for 21 days, and involves food intake in accordance with a stringent vegan diet. The purpose of the present study was to determine the effect of a 21 day Daniel Fast on biomarkers of antioxidant status and oxidative stress. Methods: 43 subjects (13 men; 30 women; 35+/-1 yrs; range: 20-62 yrs) completed a 21 day Daniel Fast following the guidelines provided by investigators. Subjects reported to the lab in a 12 hour post-absorptive state both pre fast (day 1) and post fast (day 22). At each visit, blood was collected for determination of malondialdehyde (MDA), hydrogen peroxide (H2O2), nitrate/nitrite (NOx), Trolox Equivalent Antioxidant Capacity (TEAC), and Oxygen Radical Absorbance Capacity (ORAC). Subjects recorded dietary intake during the 7 day period immediately prior to the fast and during the final 7 days of the fast. Results: A decrease was noted in MDA (0.66+/-0.03 vs. 0.56+/-0.02 umol/L; p=0.004), while H2O2 demonstrated a trend for lowering (4.42+/-0.32 vs. 3.78+/-0.21 umol/L; p=0.074). Both NOx (18.79+/-1.92 vs. 26.97+/-2.40 umol/L; p=0.003) and TEAC (0.47+/-0.01 vs. 0.51+/-0.01 mmol/L; p=0.001) increased from pre to post fast, while ORAC was unchanged (5243+/-103 vs. 5249+/-183 umol/L TE; p=0.974). As expected, multiple differences in dietary intake were noted (p<0.05), including a reduction in total calorie intake (2185+/-94 vs. 1722+/-85). Conclusion: Modification of dietary intake in accordance with the Daniel Fast is associated with an improvement in selected biomarkers of antioxidant status and oxidative stress, including metabolites of nitric oxide (i.e., NOx).
vineri, 11 martie 2011
luni, 7 martie 2011
radicali liberi
"As usual, it's a case of everything in moderation. In normal conditions, free radicals act as important signal substances, but very high levels or long-lasting increases can lead to disease"
vineri, 4 martie 2011
joi, 24 februarie 2011
vrei sa slabesti? poti sa mananci ORICE
"Eat less, while enjoying the foods you eat. Eat lots of fruits and vegetables, and lots of herbs and spices. And maybe most importantly, spend less time stressing over the types of food you are eating."
luni, 14 februarie 2011
mecinicumilmaicheama
"Răcoritoarele "light" au fost intens promovate. Toţi cei aflaţi în lupta cu kilogramele erau consolaţi că, printre atâtea restricţii, puteau să simtă gustul de zahăr fără "vina" că se va şi depune. Cine crede că băuturile dietetice nu îngraşă se înşală însă: în final, se vor îngrăşa mai mult, pentru că vor compensa mâncând mai mult din alte alimente.
"Nu poţi păcăli organismul: el va reţine caloriile pe care nu le-a primit din băuturile fals-dulci din alte surse. Tot metabolismul se dereglează", atrage atenţia specialistul Mencinicopschi."