The main health benefit of lettuce and other greens in salad is fiber. Salads are often packed with fiber, a nutrient—not just for you! Fiber is truly food for the microbiome, trillions of bacteria living in your gut. Fiber is also key to metabolic health. Bacteria in your gut convert fiber into short-chain fatty acids, which can regulate immune function and keep inflammation in check.
Add a variety of vegetables like broccoli and green peppers, and add beans and lentils to boost the fiber in your leafy green salad.
But the healthiest salads contain many other good-for-you ingredients, such as antioxidants. Antioxidants are chemicals essential for your liver that detoxify almost any environmental poison that enters the body. Your liver needs these antioxidants to perform this magic trick.
Try chopped colorful vegetables (the darker the better), chopped fresh fruits, herbs (fresh or dried), and spices for antioxidants. Next, add proteins such as free-range eggs, pastured beef, fish, chicken, tofu, beans or lentils.
Add oil and fermented foods to your salad.
Now fold in some whole-food oils, including avocado, olives, nuts, and seeds. Nuts and seeds (like chia seeds and walnuts) are packed with anti-inflammatory alpha-linolenic acid (ALA), an omega-3 fatty acid that has been shown to reduce the risk of heart disease.
For other sources of omega-3s, try small fish like anchovies (usually found in Caesar salads). You can also include other wild fish (sardines, salmon, mackerel) or chicken (free-range, pasture-raised chicken has less antibiotics)..
Cheeses are a great additive as they contain single-chain fatty acids that are protective against diabetes and heart disease. We’ve all been taught to avoid fats as they have more calories, but milk fatty acids are unique in that they contain a specific phospholipid that prevents inflammation at the ends. Just don’t use American cheese that isn’t actually cheese. Instead, try varieties like feta, cotija, parmesan, and mozzarella.
Bonus points go to kale, kale, and Brussels sprouts, which are cruciferous vegetables that can boost your body’s own natural antioxidant production and stimulate the production of liver detoxification enzymes. Another bonus: fresh tomatoes contain lycopene, an antioxidant that supports eye function and prevents cataracts.
Adding fermented foods like kimchi and sauerkraut can provide a gut-friendly boost, as can homemade sauces made with natural, unsweetened yogurt. And fermented foods already contain short-chain fatty acids.
Avoid store-bought salad dressings
Alright. Now let’s talk about salad dressings.. To make a great homemade sauce, focus on ingredients like extra-virgin olive oil, avocado oil, tahini, vinegar, Dijon, herbs, spices, and low-sugar citrus juices (lemon, lime, grapefruit).
The oleic acid in olive oil activates the liver, producing a factor that accelerates metabolism. The acetic acid in vinegar inhibits an enzyme that breaks down starches in the mouth, reducing the amount of glucose that appears in your bloodstream. Some homemade sauces get extra antioxidants from spices and seasonings like ginger, garlic, turmeric, oregano and thyme.
But the same cannot be said for most store-bought dressings. Store-bought versions are often made from canola and soybean oils, which are packed with linoleic acid, an inflammatory omega-6 fatty acid.
They can also introduce large amounts of fructose (sugar molecules) in the form of cane sugar, high fructose corn syrup, or honey that damage the mitochondria, the energy-producing factories that power each of your cells. When your mitochondria aren’t working right, your blood sugar and insulin rise, and your liver has no choice but to convert fructose into fat — leading to fatty liver and insulin resistance, potentially increasing your risk of developing heart disease, cancer and diabetes.
You might be surprised at how common it is for sugar to leach into bottled dressings. For example, high fructose corn syrup is the second ingredient in Kraft’s Creamy French sauce, which contains five grams of added sugar. And watch out for fat-free toppings—for example, Ken’s Sundried Tomato Vinaigrette has 12 grams of added sugar.
Store-bought dressings may also contain ingredients that are bad for your gut and the trillions of bacteria that reside there. These bacteria send chemical signals to your brain asking it to feed. If you don’t feed your bacteria, they actually start to feed on you – they strip the mucin, a protective layer from your intestinal cells. Over time, this can lead to irritable bowel syndrome, inflammatory bowel disease, and altered intestinal permeability, which some call “leaky gut.” It can also cause systemic inflammation.
Store-bought dressings often contain emulsifiers such as: carboxymethylcellulose, polysorbate-80, or carrageenan, block the separation of fat and water – and can dissolve the protective mucin layer in your gut. These pesky added sugars can also cause the growth of bad microbiome bacteria, potentially leading to gastrointestinal upset, gas, bloating, diarrhea and inflammation.
Croutons and crunchy stuff
But that doesn’t mean you should skip the dressing. Studies have shown that fats like avocado actually help your body absorb nutrients from certain vegetables. The key is to choose the right ingredients and ideally make your own dressing at home.
It’s also a good idea to stay away from “crunchy” things (like fried onions and tortilla strips), which are often fried in seed oils at high temperatures, where trans fats and the formation of acrylamide, a known carcinogen, pose a risk. I also suggest you be careful about nuts; some varieties and brands coat them with sugar to make them sweeter and tastier.
And finally, watch out for processed breads. A Caesar salad isn’t a Caesar salad without croutons—but commercial croutons are typically packed with preservatives, sodium, and vegetable oils. Bake your own croutons or pair your salad with a slice of sourdough bread. But please don’t eat the fried tortilla bowl.
Robert H. Lustig He is an emeritus professor of pediatrics at the University of California at San Francisco andMetabolic: The Charms and Lies of Processed Food, Nutrition, and Modern Medicine”
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