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間歇性斷食
間歇性斷食(Intermittent Fasting)可能啟動某些遺傳修復機制,促進細胞修復;這種適應能力似乎能夠在饑荒時延長某些細胞的壽命。比起分裂生長新的細胞,修復細胞需要耗損的成本較少,這種機制對於減少癌細胞形成及擴散有積極的影響。這些遺傳修復機制是由人類生長激素 (HGH) 所啟動。HGH 能夠促使新陳代謝改變,幫助燃燒脂肪及保留體內蛋白。蛋白質及胺基酸是修復組織膠原所需的物質,能夠增進肌肉、肌腱、韌帶及骨骼的功能和強度,HGH 也能增進肌膚功能、減少皺紋並加快割傷及燒傷復原。 HGH 及胰島素的功能恰好相反。HGH 主要用以組織修復、能量消耗及抗炎免疫活性;胰島素則用以儲存能量、分裂細胞及促進炎症免疫活性。胰島素佔有主導的地位,當人體對胰島素有需求時 (攝取碳水化合物時) ,HGH 即會受到抑制。 間歇性斷食是減少炎症、增強免疫力及促進組織修復最有效的方式之一,這也是為什麼許多人受到感染時會覺得噁心。這種天生的機制是人體促使我們斷食的方式,這樣才能製造可以增強自然免疫力的適當環境。 間歇性斷食 (Intermittent Fasting) 及高強度的短暫運動是幫助人體適應環境及增強生存能力所需的要素,能夠帶來強健的肌肉、鞏固的免疫系統及良好的消化。斷食 12 至 24 小時配合高強度運動能夠有效刺激人類生長激素 (HGH) 的分泌。HGH是由腦下垂體所製造的重要蛋白激素,能夠增強細胞修復功能,並調節代謝,以促進燃燒脂肪、增強肌肉並減緩壓力的負面影響。 研究人員發現,斷食 24 小時的男性血液中的 HGH 可增加達 2000%,而女性也可增加達 1300%。2009年的一項研究也顯示,乳酸堆積能夠幫助促進 HGH 分泌;乳酸只有在強烈的無氧運動過程中才會生產,有氧運動的強度並不足以產生能夠刺激 HGH的乳酸。 低強度及長時間的有氧運動會促成自然分解反應及大量的自由基(free radicals),卻不會製造幫助修復的肽、酵素及荷爾蒙,結果反而消耗身體的能量;高強度的運動也會產生自由基,但同時會觸發許多幫助修復的肽、酵素及荷爾蒙產生,於是促進組織修復,並對人體產生正面影響及抗老作用。 每週兩天輕食,其他5天正常飲食
適度的輕斷食,給身體帶來的益處遠遠超出你的想像,首先,它可以讓身體不用辛苦一直消化食物,肝臟也有時間可以修復受損細胞,進行排毒。而且,由於一週只有兩天執行輕斷食,不影響我們的生活品質,還是可以跟朋友聚會,也不需要看著別人吃美食,而自己只能很可憐地吃蔬果。你完全可以自由選擇適合輕斷食的日子,努力執行一天后,明天又可以吃想吃的食物,身體也在這天得到適當的休息與修復。而在斷食期間,你並不是完全不吃任何東西,而是將分量降到平日的1/4,實施起來非常簡單,更有利於長期執行。 |
Intermittent Fasting
Intermittent fasting (IF) is an umbrella term for various diets that cycle between a period of fasting and non-fasting. Intermittent fasting is one form of dietary restriction. Variations In some contexts, fasting allows the consumption of a limited amount of low-calorie beverages such as coffee or tea. One form of intermittent fasting, alternate day fasting (ADF), involves a 24-hour fast followed by a 24-hour non-fasting period. This is sometimes referred to as every other day fasting or every other day feeding. Alternate-day calorie restriction may prolong life span. Modified fasting involves limiting caloric intake (e.g., 20% of normal) on fasting days rather than none at all. A study suggests that this regimen may retain most of the benefits of intermittent fasting. The scientific literature for intermittent fasting, in its various forms, was extensively reviewed in 2014. Another form involves eating only one meal per day. More generally, forms may choose to specify various ratios of fasting to non-fasting periods. The BBC2 Horizon documentary Eat, Fast and Live Longer covered people who committed to fasting two non-consecutive days per week. Known as the 5:2 diet, people consumed 400–500 calories (women) or 500–600 calories (men) during the days of fasting. During feed days, the diet was regular. Research A 2014 study done by Longo and Mattson shed light on intermittent fasting's role in adaptive cellular responses that reduce oxidative damage and inflammation, optimize energy metabolism, and bolster cellular production. The study showed how, in lower eukaryotes, chronic fasting extends longevity, in part, by reprogramming metabolic and stress resistance pathways. In rodents, intermittent fasting was shown to protect against diabetes, cancers, heart disease and neurodegeneration, while in humans it helps reduce obesity, hypertension, asthma, and rheumatoid arthritis. Studies in mice and rats A scientific study of intermittent fasting in rats conducted in 1943 found that fasting rats one day out of two, three or four days prolonged the life span of rats (by 15-20% in the case of one day out of three), compared to rats that were allowed to eat whenever they wish. None of the intermittent fasting in the study had detrimental effects on growth. In one study, intermittent fasting has been shown to extend lifespan and increase resistance to age-related diseases in rodents and monkeys, and improve the health of overweight humans. The study suggests that intermittent fasting may have benefits that are similar to the effects of caloric restriction (CR). Specifically, it has been proposed that intermittent fasting improves the cardiovascular and neurological systems. One study on mice suggests that benefits from intermittent fasting seems to be unrelated to an overall reduction in caloric intake. Another study on rats dealt with the benefits of dietary restriction, including intermittent fasting. Animal health A 2007 review of alternate day fasting said, "the findings in animals suggest that ADF may effectively modulate several risk factors, thereby preventing chronic disease, and that ADF may modulate disease risk to an extent similar to that of CR. More research is required to establish definitively the consequences of ADF." A study on hypercholesterolaemic mice showed that food restriction by intermittent fasting induces diabetes and obesity and aggravates spontaneous atherosclerosis development. Non-hypercholesterolaemic (normal, wild) control mice lost fat and lowered cholesterol as expected. Human health Studies on humans suggest possible benefits: ● Intermittent fasting may function as a form of nutritional hormesis. ● Alternate-day fasting may encourage fat oxidation. ● Alternate-day fasting may reduce body weight, LDL, and triglyceride levels to the same degree regardless of maintenance of low fat or high fat diet on the feeding day. |
Intermittent fasting is a key strategy for anti-aging and longevity
Wednesday, November 30, 2011 by: Dr. David Jockers (Natural News) Our ancient ancestors grew up in a world of stress and scarcity. Food was often not available and intermittent fasting was common. This form of life left a genetic blueprint with key information pertaining to our health and wellbeing. Intermittent fasting reduces oxidative stress, enhances cellular repair processes and appears to be a key strategy for anti-aging and longevity. Thousands of years of food scarcity led our bodies to develop a protective mechanism to adapt to alternating phases of food abundance and scarcity. During times of food scarcity, our cell membranes become more sensitive to insulin. This is especially important when food is scarce because it ensures that every bit of food be efficiently used or stored. During times of food abundance the body desensitizes the cells to insulin in an effort to avoid the stress of a heavy calorie intake. This results in elevated insulin levels, increased fat storage and increased oxidative stress and inflammatory conditions in the body. Insulin also enhances cellular division, which is a risk factor for cancer formation. Today, we have a massive abundance of food sources. We can virtually eat anytime we would like. In fact, many health coaches recommend eating 5-6 small meals throughout the day. This process, however, sends the body the signal of surplus that inhibits key tissue repair hormones, which have powerful anti-aging effects. Turning on Genetic Repair Mechanisms Intermittent fasting acts to turn on certain genetic repair mechanisms that enhance cellular rejuvenation. This adaptation appears to allow certain cells to have a longer lifespan during times of famine. It is energetically less expensive to repair a cell than it is to divide and create new cells. This has a positive effect at shutting down cancer cell formation and proliferation. These genetic repair mechanisms are turned on through the release of human growth hormone (HGH). HGH is known to create physiological changes in metabolism to favor fat burning and protein sparing. The proteins and amino acids are utilized to repair tissue collagen which improves the functionality and strength of muscles, tendons, ligaments, and bones. HGH also improves skin function, reduces wrinkles & heals cuts and burns faster. HGH and insulin are opposites in function. HGH is focused on tissue repair, efficient fuel usage and anti-inflammatory immune activity. Insulin is designed for energy storage, cellular division and pro-inflammatory immune activity. Insulin is the dominant player in this game. When conditions demand an insulin release (carbohydrate intake), HGH is inhibited. Fasting is a Powerful Healing Modality Intermittent fasting is one of the most powerful modalities for reducing inflammation, boosting immunity and enhancing tissue healing. This is one of the reasons why many people feel nauseated when they have infections. This innate mechanism is the body's way of influencing us to fast so it can produce the right environment to boost natural immunity. Researchers at the Intermountain Medical Center Heart Institute found that men, who had fasted for 24 hours, had a 2000% increase in circulating HGH. Women who were tested had a 1300% increase in HGH. The researchers found that the fasting individuals had significantly reduced their triglycerides, boosted their HDL cholesterol and stabilized their blood sugar. The best way to begin fasting is by giving your body 12 hours between dinner and breakfast every single day. This allows 4 hours to complete digestion and 8 hours for the liver to complete its detoxification cycle. After this is a standard part of lifestyle, try taking one day a week and extending the fast to 16-18 hours. Eventually, you may choose to do a full 24 hour fast each week. About the author: Dr David Jockers is a Maximized Living doctor and owns and operates Exodus Health Center in Kennesaw, Georgia where he specializes in functional nutrition, functional medicine and corrective chiropractic care to get to the underlying cause of major health problems. |
The Effects of Intermittent Energy Restriction on Indices of Cardiometabolic Health (2014)
Intermittent energy restriction (IER) has become the subject of considerable scientific interest as a potential dietary approach for weight-loss and improving cardiometabolic health. This approach involves intermittent periods of total or partial energy restriction (ER) alternated with non-restricted intake, and has been studied in rodent and human populations. This review aims to provide an overview of the IER literature to date, with a specific focus on its effects on cardiometabolic health indices in rodents and humans. Current evidence from studies in rodents and humans suggests that IER is capable of promoting weight-loss and/or favourably influencing an array of cardiometabolic health indices, with equal or greater efficacy than conventional continuous ER approaches. Putative mechanisms include the effects of IER on adipose tissue physiology, stress resistance and fat distribution within visceral and intra-hepatic sites. However, a large proportion of this mechanistic evidence is limited to indirect observations and/or has come from rodent studies requiring translation into humans. Furthermore, whilst there are some indications that total IER and the array of partial IER protocols which have been developed may elicit distinct biological effects, our knowledge around this is limited as only a small number of rodent studies have directly addressed this. Ultimately, whilst much remains to be learned about IER, including its mechanisms of action and long-term efficacy, the positive findings to date serve to highlight promising avenues for future research. |