In the U.S., Mexican cuisine has become enormously popular in the past 30 years. A recent USA Today poll1 listed the 15 “Best” Tex-Mex chain restaurants in the U.S. as follows:
- Baja Fresh
- Moe’s Southwest
- On the Border
- Taco Bell
- El Pollo Loco
- Wahoo’s Fish Taco
- Chevys Fresh Mex
- Del Taco
- El Torito
- Taco Cabana
- Pappasito’s Cantina
It has certainly been argued that fast American “Mexican” food is a far cry from the authentic cuisine actually found in the 31 Mexican federal states. Genuine Mexican cooking clearly is not uniform from one area or State of the country to the next. The foods of northern Mexican States differ from those in the south which in turn vary from coastal regions. Distinctive cuisines have arisen in Oaxaca, Mexico City, Yucatan, Veracruz, Chiapas, Querétaro and other regions and reflect historical, cultural and environmental differences among these discrete geographical areas.
As with most eating traditions found worldwide, current day Mexican cuisine is derived from an amalgamation of people, cultures, historical events and available foods. Prior to the European “discovery” of the Americas by Columbus in 1492, the indigenous peoples of the area we now call Mexico were necessarily reliant upon native plant and animal foods that could either be collected wild or domesticated. Notable domesticated plant foods native to Mexico and the Americas were corn (maize), chile peppers (all varieties), tomatoes, squash, certain bean species (Phaseolus vulgaris [kidney, pinto, black and navy beans], Phaseolus lunatus [lima beans]), tomatillos, maguey (mescal), cassava, avocadoes, chocolate and potatoes, among others.
With the arrival of Europeans came the introduction of cows (beef, dairy products: milk, butter, sour cream and cheese), pigs (pork), goat, and sheep (lamb, mutton) which were rapidly incorporated into the native Mexican cuisine. Other European/Asian food introductions that are frequently found in the present day Mexican cuisine are wheat, rice, barley, hops, lettuce, onions, green onions (scallions), garlic, cilantro, limes, olives, olive oils, cumin, black pepper, vinegar, and sugar.
Regardless of the region or individual federal States, Mexican cuisine is characterized by the plant foods native to Mexico and the Americas and primarily include chili peppers (multiple varieties), tomatoes and corn (maize). Beans (pinto, black and kidney) follow a close second. Corn is most frequently made into tortillas and consumed almost daily, but also is used to make a wide variety of foods including tamales, sopes, drinks (atole, pozol) and soups. Chile peppers (all varieties) almost uniformly define Mexican cuisine as they are in one form or another (salsas, sauces, diced, chopped, pureed, dried, stuffed or pickled) included into foods and meals daily. These spicy foods add the characteristic flavor to virtually all Mexican dishes, but also the “heat” which characterizes this distinctive dining tradition.
What follows is a laundry list (obviously non-comprehensive) of Mexican dishes and beverages, some of which are found worldwide, others almost always in specific regions or federal States of Mexico:
- Chile rellenos
- Chili con carne
- Chili con queso
- Huevos rancheros
- Huevos divorciados
- Huevos motuleños
- Taco salad
- Queso flameado
- Carne asada
- Salsa verde
- Salsa roja
- Jalapeño poppers
- Black beans
- Refried beans
- Corn tortillas
- Wheat tortillas
- Corn chips
- Tortilla chips
- Hot sauce
- Fresh peppers (all varieties)
- Dried peppers (all varieties)
- Pickeled peppers (all varieties)
- Pico de gallo
- Mole sauce
- Mexican beers
- Dos Equis
- Carte Blanca
Nutritional Shortcomings of Mexican Cuisine
Almost all of us have enjoyed some of these dishes and beverages, simply because the Tex-Mex food culture pervades American fast food restaurants and supermarkets. Unfortunately many Mexican dishes which have been produced commercially or in restaurants are not Paleo for the following reasons:
- Inclusion of cereal grains (corn, wheat, rice) or beverages made from grains (beer) in daily staple foods and recipes.
- Inclusion of beans (black, pinto, kidney, lima etc.) in many recipes and meals
- Inclusion of salt (either refined or sea salt) in almost all dishes, recipes and sauces
Besides being nutritional lightweights, cereal grains2 and legumes promote increased intestinal permeability. Wheat in particular contains at least three compounds known to promote a “leaky gut” including gluten, wheat germ agglutinin (WGA), and thaumatin like proteins. Corn, like all cereal grains, is rich in antinutrients including lectins which are known to decrease intestinal absorption of many key nutrients and may cause villous flattening.2 As I have previously pointed out beans and all legumes are concentrated sources of saponins which have been demonstrated in human studies to increase intestinal permeability.
When the cells lining the gastrointestinal tract become compromised leading to increased intestinal permeability (e.g. a leaky gut), it allows the gut contents (food and microorganisms) to chronically interact with the immune system. Accordingly, many immunologists now believe that increased intestinal permeability represents an initial environmental trigger for autoimmune diseases in genetically susceptible individuals.3-7
A leaky gut also allows entry of a compound called lipopolysaccharide (LPS), found in gut gram negative bacteria, into the bloodstream. Systemically, LPS may produce a chronic low level inflammatory condition called endotoxemia, which is increasingly being recognized as an underlying factor in insulin resistance, the metabolic syndrome, cardiovascular disease and obesity.8-11
In addition to gluten containing grains, WGA and bean saponins, a number of other foods and beverages commonly included in Tex-Mex cuisine also may impair intestinal barrier function and promote a leaky gut. These foods include chili peppers, tomatillos and unripe, green tomatoes.12 Because they contain ethanol, note too that all alcoholic beverages including Mexican beers, tequila, mescal and pulque may cause a leaky gut.
Chili peppers are members of the nightshade family of plants and are among the most heavily consumed spices throughout the world. The table below shows the five most common species of chili peppers and lists a few of the more familiar varieties within each species.
Chili peppers are favorite spices throughout the world because of their pungent or “hot” taste and aroma. The “heat” from chili peppers comes from a group of compounds called capsaicinoids or capsaicins. The greater the concentration of capsaicins in the chili pepper, the “hotter” it tastes. More than 20 capsaicins are found in chili peppers, and their total concentrations range from 0% to more than 2% by weight. Daily per capita consumption of capsaicins in the U.S. and Europe is ~1.5mg whereas in India, Mexico and Thailand it is ~ 25-200mg. The table below shows the concentrations of total capsaicins in a variety of chili peppers and foods.
Chili peppers seem to have both beneficial and harmful health effects. They have long been used in Mayan and Ayurvedic healing remedies and more recently have found therapeutic application in modern medicine with pain relief. One of the potential shortcomings of chili peppers is their ability to increase intestinal permeability, and herein lies perhaps their greatest threat to human health. As far back as 1998 it was suggested by Dr. Jensen-Jarolim and colleagues13 that chili peppers, because of their capsaicins “may modulate the absorption of low molecular weight food constituents that are involved in the pathogenesis of food allergy and intolerance.” This statement simply means that chili pepper capsaicins increase intestinal permeability13-18 and, therefore, allow gut microorganisms and food proteins access to our immune systems which in turn may promote allergy, autoimmune diseases and chronic low level inflammation.
The Bottom Line with Mexican Cuisine
If you are a Paleo Dieter and like an occasional night out with friends and family at your local Tex-Mex restaurant – go for it. Enjoy your enchiladas, tacos, chili rellenos, refried beans, chips, salsa and even sip a margarita. However, try to avoid wheat flour tortillas and beer.If you decide to have a margarita, order it without salt. For Paleo Dieters even better choices on a night out might be a Mexican salad with pork, chicken or beef; or a meat/fish tostada; or how about a beef, pork, chicken or fish main dish and replace the beans, rice and tortillas with a big salad or steamed veggies.
Even the most dedicated Paleo Dieter probably would find it difficult to be 100% compliant with all foods known to increase intestinal permeability. However you don’t have to. Most people find that by being about 85% compliant with the Paleo Diet, they experience significant improvement in their health and well being. Food elements typically found in Mexican cuisine which may increase intestinal permeability (flour tortillas, chili peppers, salsa, beans, tequila, beer, green tomatoes, tomatillos) operate in a dose dependent manner meaning that all of these foods must be regularly consumed to chronically increase the risk of a leaky gut. However here’s an important exception: If you have an autoimmune disease, you should be cautious in consuming Mexican cuisine or any food known to increase intestinal permeability.
Loren Cordain, Ph.D., Professor Emeritus
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