Um estudo sobre a milagrosa molecula NAC
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3967529/GGT
How Does GGT Get Elevated in the First Place?
Not all factors that elevate GGT are well known, however some are. Certain diet patterns are associated with increased GGT, including consumption of red meat and alcohol, whereas consumption of non-fried or canned vegetables, grains, beans, tree nuts and coffee seem to be associated with lower levels of GGT[7]. Recall, GGT was higher when blood antioxidant levels were lower, therefore it makes sense that consuming an antioxidant rich diet filled with multi-colored vegetables foods is one strategy to prevent elevations in GGT!
Although this has not yet been shown in research, I speculate that Advanced Glycosylation Endproducts (See Complementary Corner December 2006) may also contribute to elevated GGT levels. (If you review the AGE article, you will find meat and fried foods amongst the highest AGE-containing foods). In general, cooked oils or fats produce oxidants, called peroxides, in the body which elevated GGT. In addition some drugs, like acetaminophen in over the counter pain medication, also deplete the antioxidant glutathione and cause elevations in GGT.
What Can I do to Protect My Liver?
The easiest answer is to follow a healthy diet, rich in tree nuts, beans, fruits and vegetables and lean animal proteins like fish and poultry. Limit red meat and avoid fried foods. When using cooking oils, use olive oil and don’t cook at high temperatures.
Some research suggests low amounts of alcohol may actually be good for people with diabetes and may improve glucose control and reduce vascular risk [8], however alcohol should be limited to no more than one drink per day for women and two drinks per day for men. Many alcoholic beverages, including beer and wine, contain significant amounts of carbohydrates, so all alcohol needs to be included in your daily carbohydrate allotments and your daily calorie requirements.
In naturopathic medicine, we refer to some foods as “liver foods” as these foods have either been shown to be protective for liver function in some way or contain nutrients required for detoxification. Some of these foods include garlic; onions; artichokes; root vegetables like parsnips, carrots and burdock; dandelion greens; and brassica-family vegetables like broccoli, mustard greens, turnips, cabbage and brussel sprouts.
Finally, although not well researched, it makes sense to me to eat organically when ever possible and avoid using plastics and harsh chemicals around the house. Although the exact influence of these household chemicals and food contaminants is not well known, I think your liver has enough to do without adding more substances to detoxify. Frankly, we are exposed to enough chemicals, like diesel exhaust, that we cannot control, so why not reduce our exposures whenever we can?
Are There Herbs or Nutrients that May Protect My Liver?
One of the most widely known “liver herbs” is milk thistle. Milk thistle contains a compound called silymarin which is a powerful antioxidant in the liver. Silymarin has been shown in human clinical research to reduce fasting blood glucose, reduce markers of inflammation in the liver and reduce hemoglobin A1c by 0.8% over a one-year period [9]. In a separate four-month study, Silymarin reduced hemoglobin A1c by 1.0% in four months (this is better than some medications!)[10]. Silymarin also reduced other liver enzymes, but unfortunately GGT was not tested in this study.
In addition to milk thistle, tumeric or Curcuma longa, the commonly used cooking spice in curries and Indian fare, has been shown to reduce GGT in animal research by reducing the oxidative stress caused by oxidize oils [11]. Curcuma may have other health benefits, including an anti-inflammatory activity and may improve insulin sensitivity. (See Complementary Corner July 2006 for more information on how some culinary spices may affect diabetes.)
N-acetylcysteine (NAC) is an antioxidant material available as a nutritional supplement; NAC is known to act as a precursor to glutathione in humans. NAC has not been well studies in humans. However in rats, NAC appears to lower GGT when challenged with high doses of alcohol and/or oxidized oils[12]. In addition, genetic experiments in mice where the gene for GGT has been removed results in the mice developing cataracts (a common complication of diabetes) and dying prematurely. If these mice are fed NAC, the animals do not develop cataracts and live a normal lifespan[13].
Vitamin E, although controversial in humans, has been shown to reduce GGT levels in diabetic rats and has been shown to reduce markers of lipid peroxides in humans[14]. Of note, the doses used to reduce peroxides in humans are much higher than doses typically used by most people; 1600-3200 IUs per day were required[15].
Conclusion
Your liver is a vital organ that assists in regulating blood glucose and in detoxifying normal and foreign wastes from the body. If the body is too burdened by outside toxins, these toxins accumulate and appear to alter biological function. GGT is an enzyme in the liver than functions to increase antioxidant status in the liver, as well as combine toxins with glutathione in order to detox harmful substances. Slight increases of GGT within the normal range appear to increase risk for diabetes and many cardiovascular complications associated with diabetes. There are numerous health habits that are associated with lower GGT levels, including eating a low red meat, low alcohol, high whole foods diet. In addition, clinical and animal research is supporting the use of botanical medicines like Tumeric and Milk Thistle in treating liver disease as well as preventing oxidative damage in the liver. In the case of Milk Thistle, this liver protection also appears to be accompanied by improvement in blood glucose control in people with diabetes. Love your liver, it’s yours to protect.