By MH Staff - Posted on 22nd January 2014
Microscopic marauders are sabotaging your efforts to lose weight. It’s time to fight back.
Except for the occasional rumbling in your tummy, you’d never know that a battle is raging deep in your gut. At stake is the size of your belly (and your love handles too). See, we all have about 5 600 strains of bacteria that toil away, breaking down food as it passes through the nine metres of our gastrointestinal tract. New science shows that the diversity and balance of your microbial troops can separate the losers from the gainers in the weight loss war. That’s because the make-up of these microbes determines how much energy you harvest from food, says Dr Gerard Mullin, director of integrative gastroenterology nutrition services at Johns Hopkins University Hospital in the US. That in turn regulates your appetite, satiety and insulin resistance. In general, the greater the variety of bugs you have, the better. For instance, scientists from Washington University School of Medicine in St Louis compared the gut bacteria of twins and their mothers and found that obese twins had less diversity than the lean twins did. Fatter folks also have a different balance of bacteria populating their insides. A study from Brazil shows that obese people have more of a bad type of bacteria called Firmicutes and less of a good kind called Bacteroidetes. Mullin and others are studying foods and behaviours that can help you recruit more good guys and flush out the bad. We tapped their research to help you keep your belly in balance.
All fibre is good at fighting fat, but a special class called prebiotic fibre is great at it. Prebiotics promote the proliferation of good bacteria in your digestive tract, says Dr Raylene Reimer, a professor of kinesiology and medicine at the University of Calgary. Here’s how it works: because you can’t digest prebiotic fibres, they pass intact through your small intestine. But when they enter your colon, bacteria feast on them and break them down into gases and short-chain fatty acids – a set-up that allows helpful bacteria to flourish. Plus, studies suggest, this process spurs the production of satiety hormones, which help you feel fuller faster. do this Various foods contain a type of prebiotic fibre called fructan. (See “Fibre Finder” below for our top 10.) To maintain good gut health, eat eight to 10 grams of prebiotic fibre a day, says Reimer. If you’re aiming to lose weight, shoot for 15 to 21g. Fibre-supplemented products, include supplemental drinks such as Nestlé’s Nutren Optimum which has 3g of prebiotic fibre per 230ml and Abbott Laboratories’ Ensure which has 2.5g inulin per 250ml glass. Dannon Activia Fibre yoghurt and Fibre One bars, can help you hit your daily target. Those two contain inulin, a fibre extracted from chicory root – one of the best natural sources of prebiotic fibre. NOTE THIS: In South Africa products do not indicate prebiotics – some supplemental drinks do, but it is not an acceptable nutrient content claim at this stage with the new legislation, says registered dietician Megan Pentz-Kluyts. If you’re looking for more fibre and prebiotics, “check your ingredient list for dietary or soluble fibre,” says Pentz-Kluyts. Or load up on healthy, tummy-friendly foods like yoghurt, wholewheat bread and fresh fruit.
Your gut bacteria respond to more than just what you put into your mouth. Every time you become riled up, they suffer. “The fight-or-flight mode you experience when stressed leads to imbalances of gut bacteria, ” says Mullin. That means more room for harmful bugs and less space for the good guys. In a new Ohio State University study, stressed-out mice showed immediate decreases in helpful-bacteria levels and an increase in several types of bacteria that may contribute to weight gain. DO THIS: Meditate to mellow out your miscreant microbes. “Even very brief practice can reduce stress,” says Dr Del Re, a health science specialist at the VA Palo Alto Health Care System. He recommends this daily session: first, set the timer on your smartphone to count down for three minutes. Then close your eyes and bring your attention inward. Take note of your feelings and body sensations. Direct your awareness to inhaling and exhaling through your nose. Imagine that you are breathing with your whole body, and try to focus on whatever sensations you’re feeling. Not your wavelength? Sign up for a dance class. Recent Australian research suggests that tango dancing rivals meditation as a stress reliever. Dance may be a particularly good tension buster because it makes you redirect both your body and mind away from negative thoughts. Of course, a strong body of research shows that any daily exercise can help slay stress.
Evolution may explain why having a diverse community of bacteria in your digestive tract is important, says Dr Johanna Lampe, a researcher at the Fred Hutchinson Cancer Research Center. Basically, your gut is like any fragile ecosystem: if you start to lose species, the habitat suffers. Several species of bacteria can carry out similar chemical reactions to process your food. If fewer of them are available to complete these reactions, metabolic changes – and weight gain – result. DO THIS: Eat probiotics. These good bacteria work best when consumed daily, says Lampe. Fermented foods such as yoghurt, kimchi (Korean cabbage) and sauerkraut all contain potentially beneficial bacteria, check out p30 for more on this. Another strategy is to pop a probiotic supplement.
You know that foods high in saturated fat, such as processed meats and cheeses, are kilojoule bombs. They’re also gut-bacteria bombs. In a study published in the journal Science, people who ate more saturated fat had higher levels of the bad kind of bugs associated with flab than those who ate less of it. That’s because saturated fat may stay intact as it passes through your intestine, according to Dutch research. And as it does, it steamrolls your good bacteria. DO THIS: Limit your saturated fat intake to 7% of daily kilojoules (that’s about 15g if you’re on a 8 400kJ diet), suggests Dr Marisa Moore, an Atlanta-based dietician. Swop in foods that have healthy fats, such as avocado instead of mayo on a sandwich, nuts instead of chips and lean cuts of meat instead of the processed kind, she says. For instance, grass-fed beef is usually lower in saturated fat than grain-fed beef (about two grams versus five grams for a 200g porterhouse steak) and has more omega-3s. A new study published in Meat Science identified eye of round as the cut with the least saturated fat. Lean meats can dry out easily, so braise them in a slow cooker or marinate them before grilling.
The antioxidants found in produce fight cancer and protect your heart. On top of that, they also boost good gut bacteria. “Many phytochemicals are produced by plants as antibiotic agents to protect the plants from infection,” says Lampe. “Those phytochemicals can have antibacterial effects in your gut too.” Against the bad bacteria, that is. DO THIS: Nosh on six cups of fruits and veggies per day and you’re on the right track. You can also drink your phytochemicals: in a Japanese study, people who sipped a cup of green tea daily for 10 days experienced a boom in flab-fighting flora. Prefer stronger stuff? A study in the American Journal of Clinical Nutrition found that men who drank about two glasses of Spanish red wine a day for 20 days showed improved concentrations of belly-off bacteria.