French Fries and Cancer Treatment
Jacob Schor, ND
June 21, 2006
French Fries may be our next new tool in treating cancer. A crazy idea, sure, but hear me out.
Remember acrylamides? The food scare that no one talks about anymore?
Four years ago Swedish scientists shocked everyone by announcing that acrylamide was present in a large number of everyday foods. Back in 1997 cows on a remote peninsula in southern Sweden began to stagger, collapse and then die. Turned out that water from a stream had leached acrylamide from a tunnel construction site and poisoned the cows.
Investigators checked acrylamide levels in the guys building the tunnel. Not knowing what normal was, they also checked a control group. Surprisingly, the control group had loads of acrylamide in their blood. More testing showed the acrylamide was coming from food. Turned out many foods contained significant amounts of acrylamide. As acrylamide is rather poisonous, this wasn't good news.
Acrylamide forms during the Maillard Browning Reaction. As food cooks amino acids react with sugars. Cooked food turns brown. The crusts on breads, pastries, pies and pizzas and the brown crisp in french fries or potato chips all result from Maillard Reactions. Acrylamide is formed when the amino acid asparagine reacts with glucose and fructose. [i] When potatoes or grain products brown during cooking, there's acrylamide forming.
Acrylamide is found in foods ranging from olives, pizza and beer to baby foods, coffee and green tea. Between 10 and 20 per cent of our exposure comes from pastries and cookies.
Acrylamide is neurotoxic; exposed workers develop numbness in their fingers and toes and prolonged exposure causes paralysis. Glycidamide, a breakdown product of acrylamide, is genotoxic; it binds to and damages DNA. Rats fed acrylamide develop oral, mammary, thyroid, adrenal, testicular and pituitary tumors. [ii] Epidemiological studies have yet to prove a link between acrylamides and human cancers. This is far from reassuring. Isolating a control group that doesn't eat browned foods may be impossible.
How dangerous is this stuff? Average people eat 1 microgram of acrylamide per kilo bodyweight per day. In a rat, 300 times that dose will cause a 10% increase in breast cancer. Above average eaters can easily eat 1/75th of the carcinogenic dose. [iii] In the world of food safety, that is a narrow safety margin. We worry about barbecued meats but most people eat only 1/10,000th and 1/25,000th of the carcinogenic dose of polyaromatic hydrocarbons.
. It will be years before we know the real risks of dietary acrylamide. The FDA started a large scale toxicology program in animals in 2004. A genotoxicity study should be published soon. Carcinogenicity studies should be completed in 2007 and neurotoxicity studies due in 2008. The food industry promises ways to prevent acrylamides formation but at this point there are no miracle solutions.
The toxic effects of acrylamide and glycidamide are the result of glutathione depletion. Recall that the body makes glutathione to protect itself from free radical damage. The process of getting cancer is simply a story of competition between the reactive oxygen species inside cells causing oxidative damage and glutathione quenching these molecules. The less glutathione present the more damage occurs. Dietary precursors such as n-acetyl-cysteine (NAC) and methionine increase glutathione and counter acrylamide danger. [iv] Taking NAC before eating might be wise.
Cancer treatment differs from cancer prevention. Increasing free radical damage in cancer cells is the goal. The resultant damage overwhelms the cancer cell's protective mechansims leading to self destruction.
Depleting glutathione in cancer cells leaves them defenseless against free radical damage and can kill cancer cells. Glutathione depletion is useful in treating prostate, [v] pancreatic, [vi] melanoma [vii] and colon cancers. [viii]
Acrylamide, because it lowers glutathione, increases the risk of getting cancer but may help kill cancer cells. It's hard to imagine that French fries are good for people, but perhaps, as they are a great source of acrylamide, they will deplete glutathione and synergistically work in conjunction with other treatments. Imagine fries as an adjunctive cancer treatment.
This French fry acrylamide thing started as a joke to add interest to this article. Yet a 1988 paper reports acrylamide is toxic to certain nerve tumors. [ix] Not fries, but other high acrylamide foods may really have merit. In the future this joke may prove serious.
[i] Stadler RH et al: Acrylamide from Maillard reaction products. Nature. 2002 Oct 3;419(6906):449-50.
[ii] Lafferty et al: Subchronic acrylamide treatment induces a tissue-specific increase in DNA synthesis in the rat. Toxicol Lett. 2004 Dec 1;154(1-2):95-103.
[iii] Toda M et al: [Recent trends in evaluating risk associated with acrylamide in foods. --Focus on a new approach (MOE) to risk assessment by JECFA--] Kokuritsu Iyakuhin Shokuhin Eisei Kenkyusho Hokoku. 2005;(123):63-7.
[iv] Kurebayashi H, Ohno Y. Metabolism of acrylamide to glycidamide and their cytotoxicity in isolated rat hepatocytes: protective effects of GSH precursors.Arch Toxicol. 2006 May 13; [Epub ahead of print]
[v] Coffey RN et al: Thiol-mediated apoptosis in prostate carcinoma cells. Cancer 2000 May 1;88(9):2092-104
[vi] Schnelldorfer T et al: Glutathione depletion causes cell growth inhibition and enhanced apoptosis in pancreatic cancer cells. Cancer 2000 Oct 1:89(7):1440-7
[vii] Pendyala L et al: Effect of glutathione depletion on the cytotoxicity of cisplatin and iproplatin in a human melanoma cell line. Cancer Chemother Pharmacol 1997;40(1):38-44
[viii] Moussavi M et al: Curcumin mediates ceramide generation via the de novo pathway in colon cancer cells. Carcinogenesis. 2006 Feb 25; [Epub ahead of print]
[ix] Tanii H et al: Cytotoxicity of acrylamide and related compounds to mouse neuroblastoma and rat schwannoma cells. Arch Toxicol. 1988;61(4):298-305.