[Script Info]
Title: 
[Events]
Format: Layer, Start, End, Style, Name, MarginL, MarginR, MarginV, Effect, Text
Dialogue: 0,0:00:06.82,0:00:09.08,Default,,0000,0000,0000,,Picture warm, gooey cookies,
Dialogue: 0,0:00:09.10,0:00:12.05,Default,,0000,0000,0000,,crunchy candies, velvety cakes,
Dialogue: 0,0:00:12.08,0:00:14.67,Default,,0000,0000,0000,,waffle cones piled high with ice cream.
Dialogue: 0,0:00:14.69,0:00:16.65,Default,,0000,0000,0000,,Is your mouth watering?
Dialogue: 0,0:00:16.67,0:00:17.87,Default,,0000,0000,0000,,Are you craving dessert?
Dialogue: 0,0:00:17.89,0:00:18.92,Default,,0000,0000,0000,,Why?
Dialogue: 0,0:00:18.95,0:00:23.68,Default,,0000,0000,0000,,What happens in the brain\Nthat makes sugary foods so hard to resist?
Dialogue: 0,0:00:23.70,0:00:27.09,Default,,0000,0000,0000,,Sugar is a general term\Nused to describe a class of molecules
Dialogue: 0,0:00:27.11,0:00:28.40,Default,,0000,0000,0000,,called carbohydrates,
Dialogue: 0,0:00:28.43,0:00:31.25,Default,,0000,0000,0000,,and it's found in a wide variety\Nof food and drink.
Dialogue: 0,0:00:31.28,0:00:34.42,Default,,0000,0000,0000,,Just check the labels\Non sweet products you buy.
Dialogue: 0,0:00:34.44,0:00:36.91,Default,,0000,0000,0000,,Glucose, fructose, sucrose,
Dialogue: 0,0:00:36.93,0:00:39.78,Default,,0000,0000,0000,,maltose, lactose, dextrose, and starch
Dialogue: 0,0:00:39.81,0:00:41.76,Default,,0000,0000,0000,,are all forms of sugar.
Dialogue: 0,0:00:41.79,0:00:43.72,Default,,0000,0000,0000,,So are high-fructose corn syrup,
Dialogue: 0,0:00:43.74,0:00:46.27,Default,,0000,0000,0000,,fruit juice, raw sugar, and honey.
Dialogue: 0,0:00:46.71,0:00:49.64,Default,,0000,0000,0000,,And sugar isn't just\Nin candies and desserts,
Dialogue: 0,0:00:49.66,0:00:51.19,Default,,0000,0000,0000,,it's also added to tomato sauce,
Dialogue: 0,0:00:51.19,0:00:55.68,Default,,0000,0000,0000,,yogurt, dried fruit,\Nflavored waters, or granola bars.
Dialogue: 0,0:00:55.70,0:00:58.66,Default,,0000,0000,0000,,Since sugar is everywhere,\Nit's important to understand
Dialogue: 0,0:00:58.69,0:00:59.88,Default,,0000,0000,0000,,how it affects the brain.
Dialogue: 0,0:00:59.91,0:01:02.25,Default,,0000,0000,0000,,What happens when sugar hits your tongue?
Dialogue: 0,0:01:02.28,0:01:05.21,Default,,0000,0000,0000,,And does eating a little bit of sugar\Nmake you crave more?
Dialogue: 0,0:01:05.75,0:01:07.32,Default,,0000,0000,0000,,You take a bite of cereal.
Dialogue: 0,0:01:07.35,0:01:10.50,Default,,0000,0000,0000,,The sugars it contains activate\Nthe sweet-taste receptors,
Dialogue: 0,0:01:10.53,0:01:12.75,Default,,0000,0000,0000,,part of the taste buds on the tongue.
Dialogue: 0,0:01:12.77,0:01:15.75,Default,,0000,0000,0000,,These receptors send a signal\Nup to the brain stem,
Dialogue: 0,0:01:15.77,0:01:19.24,Default,,0000,0000,0000,,and from there, it forks off\Ninto many areas of the forebrain,
Dialogue: 0,0:01:19.26,0:01:21.79,Default,,0000,0000,0000,,one of which is the cerebral cortex.
Dialogue: 0,0:01:21.81,0:01:25.98,Default,,0000,0000,0000,,Different sections of the cerebral cortex\Nprocess different tastes:
Dialogue: 0,0:01:26.01,0:01:27.97,Default,,0000,0000,0000,,bitter, salty, umami,
Dialogue: 0,0:01:27.100,0:01:29.80,Default,,0000,0000,0000,,and, in our case, sweet.
Dialogue: 0,0:01:29.82,0:01:33.42,Default,,0000,0000,0000,,From here, the signal activates\Nthe brain's reward system.
Dialogue: 0,0:01:33.44,0:01:37.10,Default,,0000,0000,0000,,This reward system is a series\Nof electrical and chemical pathways
Dialogue: 0,0:01:37.12,0:01:39.72,Default,,0000,0000,0000,,across several different\Nregions of the brain.
Dialogue: 0,0:01:39.75,0:01:41.04,Default,,0000,0000,0000,,It's a complicated network,
Dialogue: 0,0:01:41.06,0:01:44.48,Default,,0000,0000,0000,,but it helps answer a single,\Nsubconscious question:
Dialogue: 0,0:01:44.51,0:01:45.85,Default,,0000,0000,0000,,should I do that again?
Dialogue: 0,0:01:45.88,0:01:49.48,Default,,0000,0000,0000,,That warm, fuzzy feeling you get\Nwhen you taste Grandma's chocolate cake?
Dialogue: 0,0:01:49.50,0:01:51.38,Default,,0000,0000,0000,,That's your reward system saying,
Dialogue: 0,0:01:51.40,0:01:52.92,Default,,0000,0000,0000,,"Mmm, yes!"
Dialogue: 0,0:01:52.94,0:01:55.27,Default,,0000,0000,0000,,And it's not just activated by food.
Dialogue: 0,0:01:55.30,0:01:57.58,Default,,0000,0000,0000,,Socializing, sexual behavior, and drugs
Dialogue: 0,0:01:57.61,0:02:00.71,Default,,0000,0000,0000,,are just a few examples\Nof things and experiences
Dialogue: 0,0:02:00.73,0:02:03.28,Default,,0000,0000,0000,,that also activate the reward system.
Dialogue: 0,0:02:03.30,0:02:08.64,Default,,0000,0000,0000,,But overactivating this reward system\Nkickstarts a series of unfortunate events:
Dialogue: 0,0:02:08.67,0:02:12.30,Default,,0000,0000,0000,,loss of control, craving,\Nand increased tolerance to sugar.
Dialogue: 0,0:02:13.16,0:02:15.23,Default,,0000,0000,0000,,Let's get back to our bite of cereal.
Dialogue: 0,0:02:15.26,0:02:18.89,Default,,0000,0000,0000,,It travels down into your stomach\Nand eventually into your gut.
Dialogue: 0,0:02:18.91,0:02:19.92,Default,,0000,0000,0000,,And guess what?
Dialogue: 0,0:02:19.95,0:02:22.36,Default,,0000,0000,0000,,There are sugar receptors here, too.
Dialogue: 0,0:02:22.38,0:02:24.73,Default,,0000,0000,0000,,They are not taste buds,\Nbut they do send signals
Dialogue: 0,0:02:24.76,0:02:26.56,Default,,0000,0000,0000,,telling your brain that you're full
Dialogue: 0,0:02:26.59,0:02:28.73,Default,,0000,0000,0000,,or that your body should\Nproduce more insulin
Dialogue: 0,0:02:28.75,0:02:30.98,Default,,0000,0000,0000,,to deal with the extra sugar\Nyou're eating.
Dialogue: 0,0:02:31.60,0:02:34.54,Default,,0000,0000,0000,,The major currency\Nof our reward system is dopamine,
Dialogue: 0,0:02:34.56,0:02:37.13,Default,,0000,0000,0000,,an important chemical or neurotransmitter.
Dialogue: 0,0:02:37.15,0:02:39.66,Default,,0000,0000,0000,,There are many dopamine\Nreceptors in the forebrain,
Dialogue: 0,0:02:39.68,0:02:41.82,Default,,0000,0000,0000,,but they're not evenly distributed.
Dialogue: 0,0:02:41.84,0:02:44.62,Default,,0000,0000,0000,,Certain areas contain dense\Nclusters of receptors,
Dialogue: 0,0:02:44.65,0:02:48.31,Default,,0000,0000,0000,,and these dopamine hot spots\Nare a part of our reward system.
Dialogue: 0,0:02:48.90,0:02:51.55,Default,,0000,0000,0000,,Drugs like alcohol, nicotine, or heroin
Dialogue: 0,0:02:51.57,0:02:53.34,Default,,0000,0000,0000,,send dopamine into overdrive,
Dialogue: 0,0:02:53.37,0:02:56.42,Default,,0000,0000,0000,,leading some people\Nto constantly seek that high,
Dialogue: 0,0:02:56.45,0:02:58.17,Default,,0000,0000,0000,,in other words, to be addicted.
Dialogue: 0,0:02:58.64,0:03:03.53,Default,,0000,0000,0000,,Sugar also causes dopamine to be released,\Nthough not as violently as drugs.
Dialogue: 0,0:03:03.56,0:03:06.66,Default,,0000,0000,0000,,And sugar is rare\Namong dopamine-inducing foods.
Dialogue: 0,0:03:06.69,0:03:08.63,Default,,0000,0000,0000,,Broccoli, for example, has no effect,
Dialogue: 0,0:03:08.65,0:03:10.09,Default,,0000,0000,0000,,which probably explains
Dialogue: 0,0:03:10.11,0:03:12.81,Default,,0000,0000,0000,,why it's so hard to get\Nkids to eat their veggies.
Dialogue: 0,0:03:13.30,0:03:14.85,Default,,0000,0000,0000,,Speaking of healthy foods,
Dialogue: 0,0:03:14.88,0:03:17.69,Default,,0000,0000,0000,,let's say you're hungry\Nand decide to eat a balanced meal.
Dialogue: 0,0:03:17.71,0:03:21.32,Default,,0000,0000,0000,,You do, and dopamine levels spike\Nin the reward system hot spots.
Dialogue: 0,0:03:21.35,0:03:24.71,Default,,0000,0000,0000,,But if you eat that same dish\Nmany days in a row,
Dialogue: 0,0:03:24.73,0:03:28.97,Default,,0000,0000,0000,,dopamine levels will spike less and less,\Neventually leveling out.
Dialogue: 0,0:03:28.100,0:03:30.76,Default,,0000,0000,0000,,That's because when it comes to food,
Dialogue: 0,0:03:30.78,0:03:34.93,Default,,0000,0000,0000,,the brain evolved to pay special attention\Nto new or different tastes.
Dialogue: 0,0:03:34.96,0:03:36.06,Default,,0000,0000,0000,,Why?
Dialogue: 0,0:03:36.08,0:03:37.24,Default,,0000,0000,0000,,Two reasons:
Dialogue: 0,0:03:37.27,0:03:39.78,Default,,0000,0000,0000,,first, to detect food that's gone bad.
Dialogue: 0,0:03:39.81,0:03:42.73,Default,,0000,0000,0000,,And second, because the more variety\Nwe have in our diet,
Dialogue: 0,0:03:42.75,0:03:45.85,Default,,0000,0000,0000,,the more likely we are\Nto get all the nutrients we need.
Dialogue: 0,0:03:45.88,0:03:47.23,Default,,0000,0000,0000,,To keep that variety up,
Dialogue: 0,0:03:47.25,0:03:49.64,Default,,0000,0000,0000,,we need to be able\Nto recognize a new food,
Dialogue: 0,0:03:49.66,0:03:53.52,Default,,0000,0000,0000,,and more importantly, we need\Nto want to keep eating new foods.
Dialogue: 0,0:03:53.54,0:03:57.34,Default,,0000,0000,0000,,And that's why the dopamine levels off\Nwhen a food becomes boring.
Dialogue: 0,0:03:57.37,0:03:58.94,Default,,0000,0000,0000,,Now, back to that meal.
Dialogue: 0,0:03:58.97,0:04:02.07,Default,,0000,0000,0000,,What happens if in place\Nof the healthy, balanced dish,
Dialogue: 0,0:04:02.09,0:04:04.28,Default,,0000,0000,0000,,you eat sugar-rich food instead?
Dialogue: 0,0:04:04.31,0:04:07.32,Default,,0000,0000,0000,,If you rarely eat sugar\Nor don't eat much at a time,
Dialogue: 0,0:04:07.34,0:04:09.95,Default,,0000,0000,0000,,the effect is similar\Nto that of the balanced meal.
Dialogue: 0,0:04:09.97,0:04:13.70,Default,,0000,0000,0000,,But if you eat too much,\Nthe dopamine response does not level out.
Dialogue: 0,0:04:13.73,0:04:17.72,Default,,0000,0000,0000,,In other words, eating lots of sugar\Nwill continue to feel rewarding.
Dialogue: 0,0:04:17.74,0:04:21.13,Default,,0000,0000,0000,,In this way, sugar behaves\Na little bit like a drug.
Dialogue: 0,0:04:21.15,0:04:24.60,Default,,0000,0000,0000,,It's one reason people seem\Nto be hooked on sugary foods.
Dialogue: 0,0:04:24.62,0:04:27.51,Default,,0000,0000,0000,,So, think back to all those\Ndifferent kinds of sugar.
Dialogue: 0,0:04:27.54,0:04:30.90,Default,,0000,0000,0000,,Each one is unique,\Nbut every time any sugar is consumed,
Dialogue: 0,0:04:30.93,0:04:35.26,Default,,0000,0000,0000,,it kickstarts a domino effect in the brain\Nthat sparks a rewarding feeling.
Dialogue: 0,0:04:35.29,0:04:38.70,Default,,0000,0000,0000,,Too much, too often,\Nand things can go into overdrive.
Dialogue: 0,0:04:38.72,0:04:42.95,Default,,0000,0000,0000,,So, yes, overconsumption of sugar\Ncan have addictive effects on the brain,
Dialogue: 0,0:04:42.98,0:04:46.18,Default,,0000,0000,0000,,but a wedge of cake once\Nin a while won't hurt you.