1 00:00:01,840 --> 00:00:04,360 Speaker 1: Welcome to Brainstuff, a production of iHeartRadio. 2 00:00:06,800 --> 00:00:09,760 Speaker 2: Hey brain Stuff, Lauren vogel Bomb here with another classic 3 00:00:09,800 --> 00:00:13,800 Speaker 2: episode for you. In this one, we explore the biochemistry 4 00:00:13,840 --> 00:00:17,040 Speaker 2: of burning fat. We should note at the top here 5 00:00:17,160 --> 00:00:20,480 Speaker 2: that bodies are complicated and health is a lot more 6 00:00:20,520 --> 00:00:23,239 Speaker 2: than a number on a scale. But when we do 7 00:00:23,360 --> 00:00:28,880 Speaker 2: lose weight by burning fat, where does it go? Hey 8 00:00:28,880 --> 00:00:32,080 Speaker 2: brain stuff, Lauren vogl Bomb here. For many of us humans, 9 00:00:32,080 --> 00:00:35,040 Speaker 2: our body size and shape are things in flux from 10 00:00:35,040 --> 00:00:37,559 Speaker 2: one month to the next, depending on a host of factors, 11 00:00:37,560 --> 00:00:40,479 Speaker 2: both within and without our control. Our genes might be 12 00:00:40,520 --> 00:00:43,760 Speaker 2: a little tighter or a little looser. Our question of 13 00:00:43,800 --> 00:00:46,360 Speaker 2: the day is when we lose weight, where does that 14 00:00:46,440 --> 00:00:50,000 Speaker 2: lost weight go? The short answer is that our bodies 15 00:00:50,040 --> 00:00:53,200 Speaker 2: convert molecules in fat cells two usable forms of energy, 16 00:00:53,400 --> 00:00:56,600 Speaker 2: thus shrinking the cells. But getting this to happen isn't 17 00:00:56,600 --> 00:00:59,000 Speaker 2: just about sweating to the oldies or however you prefer. 18 00:00:59,040 --> 00:01:02,520 Speaker 1: To work out. Understanding how our bodies perform this tummy 19 00:01:02,520 --> 00:01:06,520 Speaker 1: trimming trick requires a little more detail. We know that 20 00:01:06,560 --> 00:01:09,840 Speaker 1: weight loss hinges on burning calories. Calories are the measure 21 00:01:09,880 --> 00:01:11,959 Speaker 1: of the potential energy in the food you eat in 22 00:01:12,000 --> 00:01:15,800 Speaker 1: the form of fats, proteins, and carbohydrates. If our bodies 23 00:01:15,800 --> 00:01:19,000 Speaker 1: were cars, energy would be the gas that keeps everything running. 24 00:01:19,400 --> 00:01:21,759 Speaker 1: Lounging in front of the television is like cruising the strip, 25 00:01:22,000 --> 00:01:24,440 Speaker 1: while sprinting around a track is more like drag racing 26 00:01:24,440 --> 00:01:28,200 Speaker 1: at maximum speeds. In short, more work means more energy 27 00:01:28,280 --> 00:01:30,920 Speaker 1: is needed. The body uses some of the calories we 28 00:01:31,080 --> 00:01:34,160 Speaker 1: ingest to digest that very food. Once the food is 29 00:01:34,160 --> 00:01:37,640 Speaker 1: broken down into its respective parts of carbohydrates, fats, and proteins, 30 00:01:37,880 --> 00:01:40,520 Speaker 1: it either uses the remaining energy or converts to fat 31 00:01:40,600 --> 00:01:43,840 Speaker 1: for storage in fat cells. And as doctor who fans know, 32 00:01:44,120 --> 00:01:47,280 Speaker 1: fat cells live in adipose tissue, which basically acts like 33 00:01:47,319 --> 00:01:51,800 Speaker 1: an internal gas station storing away fuel reserves. To lose weight, 34 00:01:51,920 --> 00:01:54,400 Speaker 1: you must burn more calories or of energy than you 35 00:01:54,440 --> 00:01:58,200 Speaker 1: consume to start using up that fuel reserve. Essentially, if 36 00:01:58,240 --> 00:02:00,920 Speaker 1: you're not ingesting enough calories to fuel your additional work, 37 00:02:01,120 --> 00:02:04,600 Speaker 1: your body must pull from fat stores. According to the 38 00:02:04,680 --> 00:02:07,960 Speaker 1: law of conservation of mass, matter is neither created nor destroyed, 39 00:02:08,160 --> 00:02:11,519 Speaker 1: but it may alter its form through chemical reaction. Essentially, 40 00:02:11,760 --> 00:02:13,920 Speaker 1: that tells us that while we lose mass in our 41 00:02:13,960 --> 00:02:17,000 Speaker 1: bodies by burning up fat, it doesn't just disappear, it 42 00:02:17,040 --> 00:02:20,880 Speaker 1: simply changes form. When we eat, the glucose and other 43 00:02:20,919 --> 00:02:23,840 Speaker 1: sugars harnessed from carbohydrates are the first things our bodies 44 00:02:23,919 --> 00:02:26,679 Speaker 1: use as fuel stores. The liver stores the glucose in 45 00:02:26,720 --> 00:02:29,040 Speaker 1: the form of glycogen and releases it into the bloodstream 46 00:02:29,120 --> 00:02:32,200 Speaker 1: as necessary to keep our bodies trucking a long Think 47 00:02:32,280 --> 00:02:34,920 Speaker 1: of your blood stream as an interconnected conveyor belt that 48 00:02:35,160 --> 00:02:37,639 Speaker 1: takes necessary nutrients to the body parts that need them. 49 00:02:38,160 --> 00:02:41,960 Speaker 1: Once that glucose runs out, fat takes over. Harnessing energy 50 00:02:42,000 --> 00:02:45,560 Speaker 1: by burning fat is referred to as catosis. It works 51 00:02:45,600 --> 00:02:48,920 Speaker 1: like this. Hormones regulating our blood sugar levels activate an 52 00:02:49,000 --> 00:02:51,960 Speaker 1: enzyme in the blood vessels of fat tissue called liepace. 53 00:02:52,560 --> 00:02:57,440 Speaker 1: Liepace ignites fat cells to release macromolecules called triglycerides, which 54 00:02:57,440 --> 00:03:00,880 Speaker 1: are what makes fat cells fat. Sutorides are made up 55 00:03:00,880 --> 00:03:04,400 Speaker 1: of glycerool and three fatty acid chains. When they receive 56 00:03:04,440 --> 00:03:07,040 Speaker 1: the signal from lipase to exit the fat cells, the 57 00:03:07,080 --> 00:03:10,400 Speaker 1: triglyrides break up into their respective components and enter the 58 00:03:10,400 --> 00:03:13,560 Speaker 1: bloodstream for use. The liver snatches up the glycrool to 59 00:03:13,639 --> 00:03:15,919 Speaker 1: break it down for energy, and some of the fatty 60 00:03:15,960 --> 00:03:18,000 Speaker 1: acids move to the muscles that can farm them for 61 00:03:18,120 --> 00:03:21,280 Speaker 1: energy as well. The action of breaking down triglycerides into 62 00:03:21,360 --> 00:03:24,640 Speaker 1: usable energy is called like polysis. Once the components of 63 00:03:24,639 --> 00:03:27,520 Speaker 1: the glycerol and fatty acids are inside are muscle or 64 00:03:27,560 --> 00:03:32,160 Speaker 1: liver cells, organelles called mitochondria shuffle and reshuffle those compounds 65 00:03:32,280 --> 00:03:34,960 Speaker 1: to harness their potential energy, sort of like a furnace 66 00:03:35,000 --> 00:03:39,400 Speaker 1: burns wood. The mitochondria break down and recombine those components 67 00:03:39,400 --> 00:03:43,000 Speaker 1: of our fat cells and produce heat, water, carbon dioxide, 68 00:03:43,040 --> 00:03:48,360 Speaker 1: and adenysine. Triphosphate or ATP. ATP hauls potential energy in 69 00:03:48,360 --> 00:03:51,960 Speaker 1: its molecular bonds for use. When we exercise, like intercellular 70 00:03:52,000 --> 00:03:55,560 Speaker 1: carb loading, the water exits our bodies as sweat and urine, 71 00:03:55,640 --> 00:03:59,680 Speaker 1: and we exhale the carbon dioxide. Now that the body 72 00:03:59,680 --> 00:04:02,720 Speaker 1: has really leaved fat cells of some glycerool and fatty acids, 73 00:04:02,840 --> 00:04:06,120 Speaker 1: the cells get smaller and so sell by cell, our 74 00:04:06,160 --> 00:04:15,240 Speaker 1: body shape changes. Today's episode is based on the article 75 00:04:15,320 --> 00:04:17,400 Speaker 1: when we Lose weight, Where does the lost weight Go? 76 00:04:17,520 --> 00:04:20,440 Speaker 1: On How Stuffworks dot Com, written by Kristin Conger. To 77 00:04:20,480 --> 00:04:21,800 Speaker 1: hear more from Kristin, check. 78 00:04:21,640 --> 00:04:24,680 Speaker 2: Out her podcast on Ladylife Brain Stuff is production of 79 00:04:24,680 --> 00:04:27,120 Speaker 2: I heart Radio in partnership with HowStuffWorks dot Com and 80 00:04:27,200 --> 00:04:28,360 Speaker 2: is produced by Tyler Klang. 81 00:04:28,880 --> 00:04:30,160 Speaker 1: Four more podcasts my heart 82 00:04:30,240 --> 00:04:33,440 Speaker 2: Radio, visit the iHeartRadio app, Apple Podcasts, or wherever you 83 00:04:33,480 --> 00:04:34,799 Speaker 2: listen to your favorite shows.