Dr. L: It seems like every month brings us the latest, greatest diet book. Why contribute to the glut?
Kathie: Believe me, I’m as tired of these magic formula for losing weight as anybody: “eat this number of calories or this ratio of carbs/fats/protein for Phase 1, then for Phase 2…” Almost nobody can follow these formulas for very long. Writing The Swift Diet was for me a chance to celebrate the importance of healthy whole foods, especially vegetables, fruits and legumes. I’m translating the nutritional science onto the plate. The book was also an opportunity to look at both weight-loss and digestive health through the lens of the gut, emphasizing the role of the bacteria that live there. These bacteria, called the gut microbiome or the microbiota, are necessary for digestion – we couldn’t break down plant fiber without them — but they influence so many other aspects of our being: our immune function, our hormones, even our moods! The more we learn, the more we appreciate that in health, all roads go through the gut!
Dr. L: What inspired you to take this approach?
Kathie: In the past couple of years, the research on the microbiota has gone through the roof. The old view of bacteria fixated on a relatively few invaders from the outside world that could make us sick. Now we’re learning that weight control and a smoothly functioning digestive system, the two areas that I’m focusing on, depend on a harmonious relationship between our human cells and the bacteria that live inside us. This dovetails perfectly with my experience as a clinical nutritionist for the past thirty years. So many of my clients with digestive problems – IBS-type symptoms, GERD, you name it – were also struggling with their weight. And visa versa. In The Swift Diet, I write that they’re two sides of the same coin – Irritable Bowel and “Irritable Weight.”
Dr. L: So how does the bacteria in your gut influence your weight?
Kathie: We know now that weight gain or loss can’t be reduced to simply “calories in/calories out.” Just as important as the number of calories we take in is how these calories interact with the body, including the microbiota. Scientists are still working out the precise mechanisms but one major way that a poorly chosen diet can drive up weight is through inflammation, a root cause of so many diseases. When we’re not eating enough plant fiber – vegetables, fruit, legumes — we’re not feeding the friendly bacteria in our system which in turn support the health of the lining of the gut. When those bacteria decline in number, that lining can grow porous, a condition called “leaky gut syndrome.” That opens the door for unfriendly bacteria to enter the bloodstream triggering inflammation. That can cause digestive upset inside the gut but it can also cause system-wide problems, like insulin resistance which promotes fat storage and weight gain. This isn’t an esoteric corner of microbiology anymore. A major new study in the prestigious medical journal The Lancet lists disruptions in the microbiota as one of the likely major drivers of obesity worldwide.
Dr. L: So dietary fiber is a key way to address weight and digestion?
Kathie: That’s right. The fiber superstars are the “non-starchy vegetables,” an umbrella term that covers a huge number of veggies: leafy greens, broccoli and cauliflower, asparagus, artichoke, the list goes on and so. But the plant-fiber roll call doesn’t stop there. We’ve got the so-called “starchy vegetables” like sweet potatoes and acorn squash; fruits, especially the berries; legumes like chickpeas and black beans; so-called “pseudo-grains” like quinoa and buckwheat. I call these foods the “MicroMenders” because the fiber in them helps mend the microbiota. The fiber takes up a lot of space in the gut and it slows down the release of glucose into the bloodstream, both of which help control and curb appetite. But these good foods are good in so many different ways. They’re also rich in disease-fighting vitamins, minerals and phytonutrients and they’re generally low in calories.
Dr. L: In “The Swift Diet“, you devote a fair amount of space to fermented foods like sauerkraut and yogurt which are becoming increasingly popular. Why are they such a big deal?
Kathie: The plant foods I just mentioned contain “prebiotic fibers,” that is, they contain fiber that feeds strains of bacteria that we know are important for human health. The fermented foods work somewhat differently. The nutrients in these foods are already partially broken down by bacteria from the outside world, that is, fermented, before we eat them. That’s true for sauerkraut made from cabbage, yogurt and kefir from milk, miso and tempeh from soy. Traditional societies have always valued these kinds of fermented foods and today, we know that they’re a tasty gut-health insurance policy. The latest research suggests that the “probiotic” bacteria that they carry onboard helps our “resident” bacteria do their jobs better. Probiotic supplements, made with these same sorts of bacteria, have become an increasingly accepted treatment for gut problems, especially when the microbiota has been depleted by antibiotics which, sadly, are both still way over-prescribed and present in our food supply. We even have preliminary evidence that these probiotic supplements can help with weight-loss as well.
Dr. L: What about food sensitivities? Don’t some nutritionists recommend staying away from certain high-fiber, healthy-sounding foods because they can cause gut problems and maybe even contribute to weight gain?
Kathie: We’ve recently seen some successful diet books that say just that. And you can be sure that the new microbiota research will launch a new wave of diet books that will recommend eating those very same foods for all the reasons we’ve been talking about. I walk a very careful middle path. It’s true that when a person’s microbiota is already seriously out of kilter, eating foods like beans or garlic or broccoli or apples can feed the gut bacteria too well, causing bloating, gas and digestive upset. But as I describe in the book, in most cases, the solution isn’t eliminating these foods entirely or permanently. We introduce them into the diet slowly so you can build up the resilience of the gut without triggering symptoms. The Swift Diet isn’t about shunning foods that might conceivably be challenging. It’s about wisely embracing a wide range of foods that can help solve weight and digestion problems! Seeing food as the enemy, as something thing that makes you sick or fat, will just stress you out. Eating good food should be a source of joy!
Dr. L: Is gluten a special case?
Kathie: Yes, a lot of people are better off staying away from gluten-containing foods, especially wheat, and not only people who have been diagnosed with celiac disease, the most severe reaction to gluten. In the late ‘80s, I suffered from chronic fatigue symptoms from an undiagnosed sensitivity to gluten. This was before medical science had wrapped its head around the whole idea of food sensitivities. Again, the microbiota is a key player in this story. If the bacteria in your gut aren’t numerous or diverse enough to recognize the protein compound in gluten, they’ll send the wrong signals to the immune system in your gut which will over-react, triggering an inflammatory response.
Dr. L: Speaking of nutritional hot-button issues, what does “The Swift Diet” have to say about fat in the diet?
Kathie: Important new studies suggest that saturated fat isn’t the dietary villain we once thought it was but I still advise moderation. Consider that the microbiota research is telling us that the two most potent drivers of leaky-gut syndrome are refined carbohydrates and saturated fat from animal foods. I would agree that the refined carbs, especially the added sugar in junk food and drinks, is the much bigger problem. When we overload the diet with this stuff, we’re not eating much in the way of high-fiber plant foods so we’re effectively starving our microbiota. And by the way, it’s not just saturated fat that is the potentially problematic fat. I think the mass-produced vegetable oils in processed foods are a potential health disaster. But if you stick to a mostly whole foods diet, you’ll be fine. It’s more important to eat good food, organic, and locally-grown if possible, than it is to obsess about which individual nutrient is being demonized or lionized in the press at any given moment.
Dr. L: Yours is the rare diet book with a detailed exercise program and an introduction to yoga and qi gong.
Kathie: As important as diet is, it’s not the only factor that affects our weight and our overall health. In the book, I talk about the importance of “digesting your whole life.” What I mean by that is, things like managing stress, getting regular exercise, attending to the quality of your sleep, of your relationships, they all count. And, believe it or not, they all affect your gut bacteria as well. If we’re chronically anxious and wrung-out, the stress hormones we generate will affect the balance of the microbiota and pump up inflammation, insulin resistance and weight-gain. That’s why in the last of The Swift Diet program chapters I devote a lot of attention to rebooting lifestyle: how to work out efficiently, how to get a better night’s sleep, how to lower stress with mind-body practices like yoga and qigong.