WEBVTT 00:00:06.619 --> 00:00:08.875 Conventional wisdom about diets, 00:00:08.875 --> 00:00:11.036 including government health recommendations, 00:00:11.036 --> 00:00:13.771 seems to change all the time. 00:00:13.771 --> 00:00:15.895 And yet, ads routinely come about 00:00:15.895 --> 00:00:19.917 claiming to have the answer about what we should eat. 00:00:19.917 --> 00:00:22.781 So how do we distinguish what's actually healthy 00:00:22.781 --> 00:00:26.516 from what advertisers just want us to believe is good for us? 00:00:26.516 --> 00:00:30.533 Marketing takes advantage of the desire to drop weight fast, 00:00:30.533 --> 00:00:31.892 and be stronger, 00:00:31.892 --> 00:00:32.665 slimmer, 00:00:32.665 --> 00:00:34.047 and brighter. 00:00:34.047 --> 00:00:37.656 And in the big picture, diet plans promising dramatic results, 00:00:37.656 --> 00:00:39.495 known as fad diets, 00:00:39.495 --> 00:00:43.644 are just what they seem: too good to be true. 00:00:43.644 --> 00:00:46.116 So where do diet fads even come from? 00:00:46.116 --> 00:00:47.794 While the Ancient Greeks and Romans 00:00:47.794 --> 00:00:52.231 rallied behind large-scale health regimens centuries earlier, 00:00:52.231 --> 00:00:56.530 this phenomenon began in earnest in the Victorian Era 00:00:56.530 --> 00:00:59.025 with crazes like the vinegar diet 00:00:59.025 --> 00:01:00.958 and the banting diet. 00:01:00.958 --> 00:01:04.248 Since then, diets have advised us all sorts of things: 00:01:04.248 --> 00:01:06.110 to excessively chew, 00:01:06.110 --> 00:01:07.939 to not chew at all, 00:01:07.939 --> 00:01:10.161 to swallow a grapefruit per meal, 00:01:10.161 --> 00:01:12.061 non-stop cabbage soup, 00:01:12.061 --> 00:01:14.247 even consumption of arsenic, 00:01:14.247 --> 00:01:16.825 or tapeworms. 00:01:16.825 --> 00:01:19.780 If the idea of diet crazes has withstood history, 00:01:19.780 --> 00:01:22.108 could this mean that they work? 00:01:22.108 --> 00:01:24.682 In the short-term, the answer is often yes. 00:01:24.682 --> 00:01:26.157 Low-carbohydrate plans, 00:01:26.157 --> 00:01:29.182 like the popular Atkin's or South Beach diets, 00:01:29.182 --> 00:01:32.312 have an initial diuretic effect. 00:01:32.312 --> 00:01:35.628 Sodium is lost until the body can balance itself out, 00:01:35.628 --> 00:01:39.063 and temporary fluid weight loss may occur. 00:01:39.063 --> 00:01:42.584 With other high-protein diets, you might lose weight at first 00:01:42.584 --> 00:01:44.670 since by restricting your food choices, 00:01:44.670 --> 00:01:47.893 you are dropping your overall calorie intake. 00:01:47.893 --> 00:01:53.396 But your body then lowers its metabolic rate to adjust to the shift, 00:01:53.396 --> 00:01:55.838 lessening the diet's effect over time 00:01:55.838 --> 00:01:59.959 and resulting in a quick reversal if the diet is abandoned. 00:01:59.959 --> 00:02:02.987 So while these diets may be alluring early on, 00:02:02.987 --> 00:02:06.879 they don't guarantee long-term benefits for your health and weight. 00:02:06.879 --> 00:02:09.967 A few simple guidelines, though, can help differentiate between 00:02:09.967 --> 00:02:13.927 a diet that is beneficial in maintaining long-term health, 00:02:13.927 --> 00:02:17.410 and one that only offers temporary weight changes. 00:02:17.410 --> 00:02:18.983 Here's the first tipoff; 00:02:18.983 --> 00:02:22.234 If a diet focuses on intensely cutting back calories, 00:02:22.234 --> 00:02:24.621 or on cutting out entire food groups, 00:02:24.621 --> 00:02:27.219 like fat, sugar, or carbohydrates, 00:02:27.219 --> 00:02:29.597 chances are it's a fad diet. 00:02:29.597 --> 00:02:32.218 And another red flag is ritual, 00:02:32.218 --> 00:02:36.532 when the diet in question instructs you to only eat specific foods, 00:02:36.532 --> 00:02:38.523 prescribed combinations, 00:02:38.523 --> 00:02:41.621 or to opt for particular food substitutes, 00:02:41.621 --> 00:02:45.130 like drinks, bars, or powders. 00:02:45.130 --> 00:02:47.768 The truth is shedding pounds in the long-run 00:02:47.768 --> 00:02:51.235 simply doesn't have a quick-fix solution. 00:02:51.235 --> 00:02:54.808 Not all diet crazes tout weight loss. 00:02:54.808 --> 00:03:00.313 What about claims of superfoods, cleanses, and other body-boosting solutions? 00:03:00.313 --> 00:03:01.893 Marketing emphasizes the allure 00:03:01.893 --> 00:03:05.852 of products associated with ancient and remote cultures 00:03:05.852 --> 00:03:08.878 to create a sense of mysticism for consumers. 00:03:08.878 --> 00:03:12.414 While so-called superfoods, like blueberries or acai, 00:03:12.414 --> 00:03:14.958 do add a powerful punch of nutrients, 00:03:14.958 --> 00:03:19.979 their super transformative qualities are largely exaggeration. 00:03:19.979 --> 00:03:22.525 They are healthy additions to a balanced diet, 00:03:22.525 --> 00:03:26.873 yet often, they're marketed as part of sugary drinks or cereals, 00:03:26.873 --> 00:03:30.059 in which case the negative properties outweight the benefits. 00:03:30.059 --> 00:03:33.307 Cleanses, too, may be great in moderation 00:03:33.307 --> 00:03:35.950 since they can assist with jumpstarting weightloss 00:03:35.950 --> 00:03:40.033 and can increase the number of fresh fruits and vegetables consumed daily. 00:03:40.033 --> 00:03:41.803 Scientifically speaking, though, 00:03:41.803 --> 00:03:45.058 they've not yet been shown to have either a long-term benefit 00:03:45.058 --> 00:03:51.047 or to detox the body any better than the natural mechanisms already in place. 00:03:51.047 --> 00:03:52.497 Everywhere we look, 00:03:52.497 --> 00:03:55.263 we're offered solutions to how we can look better, 00:03:55.263 --> 00:03:56.646 feel fitter, 00:03:56.646 --> 00:03:58.674 and generally get ahead. 00:03:58.674 --> 00:04:00.223 Food is no exception, 00:04:00.223 --> 00:04:04.686 but advice on what we should eat is best left to the doctors and nutritionists 00:04:04.686 --> 00:04:07.812 who are aware of our individual circumstances. 00:04:07.812 --> 00:04:11.388 Diets and food fads aren't inherently wrong. 00:04:11.388 --> 00:04:14.380 Circumstantially, they might even be right, 00:04:14.380 --> 00:04:17.527 just not for everyone all of the time.