Month: May 2011

Low-Fat, Plant-Based Diet Helps Prevent Skin Cancer

Every sum­mer, we hear lots of advice to use sun­screen and wear hats and so on to help us avoid skin can­cer. No one ever both­ers to tell us that eat­ing a low-fat, plant-based diet also helps to pre­vent skin can­cer.

This arti­cle, which was pub­lished in 1994 in the New Eng­land Jour­nal of Med­i­cine, stud­ied the effect of a dietary change (a switch to a low­er-fat diet) on peo­ple who had had at least one non-melanoma skin can­cer. The peo­ple who switched to a low­er-fat diet were less like­ly to get new pre­can­cer­ous lesions. A fol­low-up study pub­lished in 1998 showed that they were also less like­ly to get skin can­cers.

A prop­er diet might also help reduce the risk of melanoma, which is the most dead­ly form of skin can­cer. Eat­ing too much polyun­sat­u­rat­ed fat increas­es the risk of can­cer in gen­er­al and melanoma in par­tic­u­lar. Peo­ple who drink too much alco­hol and don’t eat enough veg­eta­bles are also at high­er risk for melanoma.

Pho­to by Joe Shlabot­nik

Varicose Veins Result From Constipation, Not From Pregnancy

If you do an Inter­net search on vari­cose veins, you’ll prob­a­bly find lots of arti­cles that claim that the cause of this con­di­tion is com­pli­cat­ed or mys­te­ri­ous. Preg­nan­cy is usu­al­ly cit­ed as a risk fac­tor. Yet Denis Par­sons Burkitt found that vari­cose veins were prac­ti­cal­ly nonex­is­tent in Ugan­da, even though many of the women in Ugan­da had borne many chil­dren.

The peo­ple in Ugan­da, like many oth­er pop­u­la­tions in the Third World, were eat­ing an extreme­ly high-fiber diet based on unre­fined starch­es and veg­eta­bles. As a result, they pro­duced large, soft stools that were easy to pass. In con­trast, Euro­peans and Amer­i­cans tend to eat a low-fiber diet with a lot of processed foods and dairy prod­ucts. As a result, their stools were small, hard, and dif­fi­cult to pass. The pres­sure that is gen­er­at­ed with­in the body when peo­ple try to pass these hard pel­lets can cause seri­ous dam­age, includ­ing diver­tic­u­lo­sis, vari­cose veins, hem­or­rhoids, hiatal her­nia, and uter­ine pro­lapse.

In oth­er words, your vari­cose veins spell out “I’ve been con­sti­pat­ed” in swollen pur­ple let­ters. How embar­rass­ing!

Needless Tragedy: Multiple Sclerosis and Jacqueline du Pré

The movie Hilary and Jack­ie tells the trag­ic sto­ry of a lit­tle girl (Jacque­line du Pré) who grew up to be one of the world’s great­est cel­lists, only to have her musi­cal career and then her life cut short by mul­ti­ple scle­ro­sis. The tru­ly sick­en­ing part of the sto­ry is that the impor­tance of diet in arrest­ing the devel­op­ment of that debil­i­tat­ing and some­times fatal dis­ease had been pub­lished long before du Pré start­ed hav­ing symp­toms of the dis­ease. Trag­i­cal­ly, the med­ical pro­fes­sion is still large­ly ignor­ing the role of a strict, low-fat diet in arrest­ing mul­ti­ple scle­ro­sis.

Pho­to by amadeusrecord

We’ve Known Since the 1930s: Fatty Diets Cause Insulin Resistance

This graph shows the glu­cose tol­er­ance test results of a healthy per­son on a high-fat test diet as opposed to a high-carb diet. Notice that he had low­er, more sta­ble blood sug­ar lev­els after eat­ing a high-carb diet!

Low-carb gurus have been telling peo­ple that insulin resis­tance, which is the under­ly­ing cause of type 2 dia­betes, results from eat­ing too much car­bo­hy­drate. Yet sci­en­tists have known since the 1930s that the prob­lem can be pro­voked by a high-fat diet and reversed by a starchy, low-fat diet. You can read the research for your­self here.

This work was done in the 1930s. How long will it take before the low-carb gurus hear about it?

French and Japanese Paradoxes

By now, you’ve cer­tain­ly heard about the “French Para­dox,” a dream that entered Amer­i­can con­scious­ness in 1991, when it was described on the tele­vi­sion pro­gram 60 Min­utes. Accord­ing to this dream, drink­ing red wine will pro­tect you from heart dis­ease, even if you eat lots of high-fat, high-cho­les­terol food. Although the risk of heart dis­ease was low­er in France than in Britain, the dif­fer­ence was not due to some mag­i­cal prop­er­ties of wine. It was due part­ly to under-report­ing of coro­nary artery dis­ease as a cause of death and part­ly due to a time-lag effect. It takes a while for a fat­ty diet to clog up your arter­ies, and the French hadn’t been eat­ing as much fat as the British had been eat­ing for as long as the British had been eat­ing it. These expla­na­tions had been pub­lished in the British Med­ical Jour­nal in 1999. You can read the arti­cle for free here.

If you want to elim­i­nate your risk of heart attack, not just decrease it a lit­tle, you’d eat a low-fat, pure­ly plant-based diet.

Alco­holic bev­er­ages, includ­ing wine, can have sev­er­al effects that influ­ence a person’s risk of dying of a heart attack. Winos who die of cir­rho­sis of the liv­er often have amaz­ing­ly clean arter­ies. That’s because their liv­er lost the abil­i­ty to make cho­les­terol. Even mod­er­ate intake of alco­holic bev­er­ages can have sev­er­al effects on coro­nary artery dis­ease. The antiox­i­dants in some alco­holic bev­er­ages, includ­ing wine, could pre­vent LDL cho­les­terol from becom­ing oxi­dized, and thus could help reduce the buildup of ath­er­o­scle­rot­ic plaque. Of course, you could get these same antiox­i­dants from plant foods that haven’t been fer­ment­ed. Alco­hol can also thin the blood, and thus help to decrease the chance of a fatal heart attack or ischemic stroke. On the oth­er hand, it would increase the risk of a fatal hem­or­rhage. I haven’t seen any con­vinc­ing evi­dence that adding any form of alco­hol to a low-fat, plant-based diet would pro­vide any health ben­e­fits.

The French para­dox turned out to be a myth. How­ev­er, there are some Japan­ese para­dox­es that are real. One involves cig­a­rette smok­ing. The oth­er involves obe­si­ty and dia­betes.

Japan­ese smok­ers are less like­ly than Amer­i­can smok­ers to get lung can­cer. This is called the Japan­ese Smok­ing Para­dox. Some peo­ple think that it’s because Japan­ese are smok­ing safer cig­a­rettes or have some mag­i­cal pro­tec­tive genes. The more ratio­nal expla­na­tion is that the Japan­ese have been eat­ing less fat and ani­mal pro­tein and more veg­eta­bles than Amer­i­cans have been eat­ing. Eat­ing the tra­di­tion­al Japan­ese diet, as opposed to the stan­dard Amer­i­can diet, helps to pro­tect peo­ple against many kinds of can­cer, not just lung can­cer.

Anoth­er para­dox involves Japan­ese chil­dren. Over the past few decades, Japan­ese chil­dren have been get­ting fat­ter, and the inci­dence of type 2 dia­betes among Japan­ese chil­dren has been going up. This has been hap­pen­ing even though their calo­rie intake hasn’t increased sig­nif­i­cant­ly. They have been eat­ing a lot more fat and ani­mal pro­tein. In oth­er words, they’ve been get­ting a small­er per­cent­age of their calo­ries from car­bo­hy­drates, which were main­ly in the form of white rice. So why do the low-carb gurus keep telling me that we need to eat more fat and less car­bo­hy­drate? Is this anoth­er para­dox? If so, what should we call it?

Lessons From Slavery: Malnutrition and Rickets Stunt Children’s Growth

Here’s an inter­est­ing arti­cle about research that attempt­ed to fig­ure out exact­ly why Black children’s growth was so bad­ly stunt­ed in the 19th cen­tu­ry Unit­ed States. It con­clud­ed that most of the stunt­ing was due to gen­er­al mal­nu­tri­tion. The growth of some dark-skinned chil­dren, espe­cial­ly in the north­ern states, could also have been lim­it­ed by short­ages of vit­a­min D, the sun­shine vit­a­min.

To Cure Obesity, “Eat Less Fat and More Starch”

Here’s an inter­est­ing arti­cle about the Pima Indi­ans of Ari­zona.

For about 2000 years, the Pima had been grow­ing corn, beans, and squash on irri­gat­ed land in Ari­zona. As a result, their tra­di­tion­al diet was high in starch and fiber and low in fat (~15% by calo­rie). After white set­tlers divert­ed the Pima’s irri­ga­tion water, the Pima had to fall back on the lard, sug­ar, and white flour sup­plied to them by the U.S. gov­ern­ment. After World War II, the Pima adopt­ed a diet that close­ly resem­bles the stan­dard Amer­i­can diet. It is low in fiber and gets about 40% of its calo­ries from fat. As a result, they have hor­rif­i­cal­ly high rates of obe­si­ty and type 2 dia­betes. In con­trast, their blood rel­a­tives in Mex­i­co who have kept more or less to their tra­di­tion­al diet have rel­a­tive­ly low rates of obe­si­ty and dia­betes.

Some low-carb gurus have tried to twist the Pima’s sto­ry into a jus­ti­fi­ca­tion for eat­ing less car­bo­hy­drate and more fat. In real­i­ty, it pro­vides strong encour­age­ment for peo­ple to eat more starch and fiber and a lot less fat.

Pigs are a “mixing vessel” for new strains of flu

The influen­za virus­es that cir­cu­late dur­ing an ordi­nary flu sea­son are bad enough. But every so often, a new and more dan­ger­ous strain of influen­za virus starts cir­cu­lat­ing. The worst strains of flu are hybrids of ordi­nary flu virus­es with strains that don’t nor­mal­ly infect human beings. Some researchers believe that the dan­ger­ous new strains of flu arise when unre­lat­ed strains of flu virus meet and swap genes in domes­tic pigs.

There are two basic ways in which a new strain of the flu can get start­ed. One is through ordi­nary muta­tion. Influen­za virus­es mutate incred­i­bly fast because their genes are in a sin­gle strand of RNA. With­out the “back­up copy” that you find in dou­ble-strand­ed DNA, they can’t use their host cell’s proof­read­ing equip­ment to find and cor­rect copy­ing mis­takes in their genes. Here’s a tech­ni­cal expla­na­tion, for peo­ple who like math. It explains why influen­za virus­es mutate about 300 times faster than poliovirus and even about 10 times as fast as HIV.

Nor­mal­ly, an unsta­ble genome would be a bad thing. That’s because most muta­tions are harm­ful to the virus itself. A virus with an unsta­ble genome would tend to die out unless it repro­duced itself in large num­bers very quick­ly and had the abil­i­ty to recom­bine with relat­ed virus­es. But under those cir­cum­stances, the genet­ic insta­bil­i­ty turns into an advan­tage! It enables the virus to stay one step ahead of the host’s immune sys­tem. We can get the flu again and again because the flu that’s going around this year is a lit­tle bit dif­fer­ent from the strain that went around last year. The anti­bod­ies we made last year aren’t a per­fect match for this year’s flu.

The very worst flu strains are the ones that are rad­i­cal­ly dif­fer­ent from the ones that had been going around in ear­li­er years. They can infect more peo­ple and cause a more seri­ous ill­ness. These pan­dem­ic flu strains seem to rep­re­sent a com­bi­na­tion of genes from dif­fer­ent strains of flu: some ordi­nary human flu strains plus some unfa­mil­iar type of flu that nor­mal­ly infects wild birds. That’s why there’s been so much hys­te­ria late­ly about “avian flu.” Pigs seem to be a per­fect “mix­ing ves­sel” for new and dead­ly strains of flu, such as the “swine flu” that caused mil­lions of deaths at the end of World War I.

Pre­vent­ing future flu pan­demics would be sim­ple. All we have to do is stop rais­ing domes­tic poul­try and domes­tic swine. At the very least, the use of antivi­ral drugs in agri­cul­ture should be banned. Oth­er­wise, they will no longer be use­ful against flu.

Ask the California State Senate to Require Nutrition Education for MDs

The Cal­i­for­nia State Sen­ate is con­sid­er­ing leg­is­la­tion to require doc­tors to learn about nutri­tion if they want to keep their license to prac­tice med­i­cine. Yes, state leg­is­la­tures can do that! Here’s the text of SB 380. If you live in Cal­i­for­nia, ask your state sen­a­tor to sup­port it. If you don’t live in Cal­i­for­nia but have friends in Cal­i­for­nia, ask them to ask their state sen­a­tor to sup­port it.

In a hear­ing about this leg­is­la­tion, John McDougall, MD, said,

The joke is that a doc­tor and his sec­re­tary know the same about nutri­tion unless she is on a diet, in which case she knows more. … If you cor­rect what’s mak­ing peo­ple sick, they get well.

The Cal­i­for­nia Med­ical Asso­ci­a­tion oppos­es the mea­sure. Of course they do. Their rep­re­sen­ta­tive sug­gest­ed that oph­thal­mol­o­gists and ortho­pe­dic sur­geons don’t need to get this train­ing. She’s some­how ignor­ing the fact that our major caus­es of new cas­es of blind­ness and vision loss are dia­betes, mac­u­lar degen­er­a­tion, and cataracts, all of which are strong­ly linked to diet. Oph­thal­mol­o­gists should know this. The joint dis­eases that cause peo­ple to end up get­ting a knee replace­ment are large­ly dietary. Ortho­pe­dic sur­geons should know this. The CMA hasn’t made sure that they learn it. The state gov­ern­ment can demand that doc­tors learn it if they want to keep their license.

It would be in the best inter­est of the peo­ple of Cal­i­for­nia for their doc­tors to get prop­er train­ing in nutri­tion. There­fore, the Cal­i­for­nia leg­is­la­ture should use its pow­er to reg­u­late the med­ical pro­fes­sion to insist that doc­tors get this train­ing. That’s why the state gov­ern­ments were giv­en the pow­er to reg­u­late the med­ical pro­fes­sion to begin with!

Watch the tes­ti­mo­ny here.

Pho­to by JasonD­Great

Dietary Therapy for Ankylosing Spondylitis

When peo­ple get sick, the cause is usu­al­ly their genes or some­thing in the envi­ron­ment or some com­bi­na­tion of the two. For many of our com­mon autoim­mune dis­eases, the cause is prob­a­bly a com­bi­na­tion of genes and diet.

In 2001, a Ger­man med­ical jour­nal pub­lished a case study of a patient who had a dou­ble dose of the gene that increas­es people’s risk of get­ting anky­los­ing spondyli­tis, a form of inflam­ma­to­ry arthri­tis that attacks the spine. He’d been sick for about 10 years and had got­ten lit­tle relief from all the drugs and oth­er treat­ments he’d tried. Nev­er­the­less, he start­ed feel­ing dra­mat­i­cal­ly bet­ter with­in a mat­ter of days after start­ing a pure­ly plant-based diet. When he went back to eat­ing meat again sev­er­al weeks lat­er, his symp­toms flared up again. When he went back to eat­ing a pure­ly plant-based diet, his con­di­tion improved so much that he was able to stop tak­ing most of his med­ica­tion.

Yes, I know that this is just a case study, but its results are con­sis­tent with the results of oth­er kinds of clin­i­cal stud­ies and they make sense in terms of the biol­o­gy. In that con­text, a case study like this, which shows that a sim­ple and gen­er­al­ly ben­e­fi­cial inter­ven­tion can pro­duce such dra­mat­ic improve­ments, should inspire some­one to do a large, well-designed clin­i­cal tri­als. Sad­ly, when I went to www.clinicaltrials.gov to see what kind of research was being done on anky­los­ing spondyli­tis, I found lots and lots of drug stud­ies but no dietary stud­ies. How can researchers jus­ti­fy giv­ing peo­ple pow­er­ful and dan­ger­ous drugs before find­ing out whether the prob­lem can be solved in a mat­ter of days with a sim­ple change in diet?

Pho­to by planetc1