Transcript for:
Guide on Intermittent Fasting and Time-Restricted Eating

hi guys welcome to my video on intermittent  fasting and time restricted eating fasting   is one of the hottest diets out there if you want  to call it a diet i'm gonna break this video into   seven sections and dissect the science to separate  the facts from fiction in part one we'll define   what intermittent fasting is part two we'll  discuss the types of fasting part three how to   fast part four the health benefits of fasting part  five fasting for weight loss part six the fasting   meal plan and finally in part seven we'll answer  the question is fasting safe for everyone so i'm   excited to get this thing rolling but before we  get started remember there is no perfect diet for   everyone each person is an individual with unique  genetics and we all have our different lives with   that being said there are some overarching  principles that apply to big groups of people   and generally speaking these are what develop  into our nutrition guidelines fasting may suit   some of you but not all of you and just to be  clear as we go through these videos and i refer   to the term fasting that's going to refer to both  intermittent fasting and time restricted eating   unlike intermittent fasting time restricted eating  does not involve caloric restriction so with time   restricted eating you can eat as much as you want  as long as you eat within that window now that   we understand those definitions let's hone in on  the science of fasting in general when you eat a   normal meal glucose from carbohydrates and fatty  acids from fats are the main energy sources for   your cells after you've eaten glucose is used as a  direct source of energy and fatty acids are stored   in your fat tissue in the form of triglycerides  when you fast meaning you're eating nothing or   very little your body runs out of glucose and  needs an alternative source of energy to keep   going it now breaks down your triglycerides into  their individual components which are fatty acids   and glycerol and then your liver will convert the  fatty acids into ketone bodies ketone bodies or   ketones for short can be used as an alternative  source of energy for many tissues including the   brain when you're eating enough food from all  three macronutrient groups meaning carbohydrates   proteins and fats the amount of ketones in your  blood are low when you fast this level rises   within the first eight to twelve hours reaching  levels between 0.2 to 0.5 millimolars which are   maintained for about 24 hours with a subsequent  increase to one to two millimolars by around 48   hours however fuel is not ketones only function  they also have major effects on your cells and   organs for example intermittently having higher  levels of ketones does four things for one it   improves mitochondrial function mitochondria are  often referred to as the powerhouses of our cells   energy in our body is mainly from the process of  mitochondria releasing energy from atp molecules   when we suffer from metabolic disturbances and  obesity our mitochondrial function is reduced   but fasting may help to improve this function two  ketones help your cells become more resistant to   stress during these times of food restriction  the cells adopt a stress resistance mode   essentially you're making your cells tougher so  they can withstand more three ketones enhance   autophagy autophagy autophagy tomato tomato  auto in latin means self and feige means eating   so this means self eating this refers to when  cells purposely eat other cells in your body   which sounds like a horrible thing but it's not  autophagy gives your cells the ability to clean up   cellular garbage if you will that cellular garbage  that normally accumulates in our cells or when   you're hurt or when you're sick basically it's  your cell's version of taking out the trash when   autophagy doesn't work properly your immune system  attacks the cellular garbage and this causes a   low-grade chronic inflammation which is the basis  of most chronic diseases the four things that   ketones do is they help recovery when you eat or  break your fast the body is forced to switch from   fasting and using ketones to glucose now this is  known as metabolic switching depending on what you   eat there will be an increase in glucose and your  ketone levels will decrease in the recovery period   there's an increase in the formation of proteins  and in this phase we see cell growth including   mitochondrial growth as well as cell plasticity  which is the ability of your cells to adapt to   changes in their environment the metabolic  switching between fuel sources links fasting   to a number of long-term health benefits the key  though is not to stay in ketosis indefinitely like   what you do with the keto diet but to regularly  swap between ketones and glucose additional health   benefits come into play because fasting goes hand  in hand with our circadian rhythm your circadian   rhythm is your body's natural clock that links  biological processes to day and night you could   think of almost every cell in your body as having  a tiny biological clock that syncs up with the   master clock located in your hypothalamus in  the center of your brain your master clock sends   signals to the body clocks throughout the day to  regulate your daily activities the master clock is   very sensitive to light and having appropriate  exposure to light during waking hours helps to   keep you alert as night falls the brain clock  initiates the production of melatonin helping to   lull you to sleep although your sleep wake cycle  is the most prominent circadian rhythm these body   clocks play a role in virtually every system in  your body research is ongoing but evidence has   connected them to metabolism and weight gain or  weight loss through the regulation of blood sugar   and cholesterol it's also part of the reason why  for most people as they become more and more tired   their food cravings become more and more intense  circadian rhythm also plays a role in influencing   mental health immunity and dna repair and thus  cancer risk this is why keeping your body aligned   with its natural circadian rhythm is ideal and  fasting plays a part in this because when done   correctly it encourages eating during the daytime  hours and fasting during the nighttime hours   there was a great study that was done in  2020 that provides us with more evidence for   sinking our circadian patterns with our eating  habits they found that when eating during daylight   hours subjects had one lower post meal blood sugar  and insulin levels two lower fat production and   three better blood pressure control interestingly  this was independent of the macronutrient content   of the diet in short it didn't matter what these  meals are made of this study highlights that when   it comes to fasting favoring one macronutrient  over another is of less significance so even   though the common practice of no carbs after  7 pm might have some value it's better to not   demonize carbs and instead get into the habit of  not eating late at night many people eat almost   half of their calories at night and we know that  nighttime eating has long been associated with   higher risk for obesity diabetes and even  cardiovascular disease this may be why breakfast   skippers who compensate by eating late at night  are metabolically worse off even though they may   not be eating more calories or gaining weight the  type of fasting that you use and how well it sinks   to your circadian rhythm may contribute towards  your success the bottom line is that people   should fast or drastically reduce their calories  enough so that your body switches to ketones for   energy for a predetermined amount of time but you  shouldn't stay in ketosis indefinitely the key to   the health benefits associated with fasting is  that metabolic switching between ketones and   glucose as an energy source giving you the best  of both worlds in addition to that ideally you   want to eat during a certain window during the  day first up is time restricted eating so this   involves two of the most popular versions there's  the 16 to 8 version where it's 16 hours of fasting   mixed with eight hours of eating and then there's  also the 12 and 12 so 12 hours of fasting 12 hours   of eating this one is also known as the circadian  rhythm version of that basically you're going to   follow a meal plan within a designated time frame  and then when you're not in that time frame when   you're in the fasting window you're going to make  sure that you don't eat or drink anything except   for water except for coffee if it doesn't have any  milk or cream or sugar in it and same goes for tea   sinking your eating during the daylight hours  is ideal in order to get the best results a   study conducted by the university of alabama  found that when a small group of pre-diabetic   men ate all their meals between 7 a.m and 3 p.m  they had significantly better insulin sensitivity   and reduced blood pressure in comparison to their  peers who ate their meals over a 12-hour period   like from 7 a.m to 7 p.m neither group gained or  lost weight but the early time restricted feeding   group showed improved metabolic health and to  sweeten the deal this group also felt more full   this shows us that meal timing does play a role  in metabolic health independent of weight loss so   if you're choosing between the 16 to 8 or the 12  to 12 or even something in between like 14 to 10   the key is to time it so that that  window avoids eating late at night   the second type of fasting is called periodic  fasting which is a little different on non-fasting   days there are technically no restrictions and  you're encouraged to eat until you feel full   on your fasting days you either eat nothing or  restrict your caloric intake anywhere from zero to   forty percent of your usual intake this fasting  will take place on one to two non-consecutive   days per week so for example on a monday and a  wednesday this method technically requires calorie   counting if you do end up eating small amounts  on fasting days or you could roughly estimate it   by only eating one small meal and last up we have  alternate day fasting here you alternate between   days of eating normally with days of eating  just one small meal an example could be where   you fast on monday wednesday and friday but then  eat without restriction on the other days this   modified alternate day fasting or madf encourages  fasting days for three to five times per week   so as you can see there's a number of ways  that you can fast so that it suits your needs   okay although the various forms of fasting sound  pretty simple i mean how hard is it to just stop   eating right but the truth is there's a trick to  fasting properly and it's not by going cold turkey   remember if you are serious about fasting and  you want to make it part of your new lifestyle   it should be viewed not simply as a fad diet  researchers have suggested that you taper down   your eating hours over a period of four months  let's first take a look at the more simple of   the two methods time restricted eating remember  that with time restricted eating you're going to   slowly decrease your window of eating and increase  your window of fasting the aim is to eat to hunger   during your eating window and eat nothing and  only drink non-caloric drinks like water and   black unsweetened tea and coffee during your  fasting period it's best to taper things down   one month at a time you don't want to rush things  here instead give your body time to adjust think   of it as a marathon not a sprint let's go  through some practical steps to help you set   out your individual plan the first thing you need  to decide is what time you want to break your fast   remember that eating earlier and ending earlier  seems to be better but this also needs to fit into   your schedule so adapt it in a way that's best  suited for you for example one way to do it is in   your first month you can fast for 10 hours per day  from monday through friday where you start eating   at 9am and then you end your eating window by 7  pm then on saturday and sunday you eat normally   then in month two you would decrease the eating  window to eight hours so keep your same monday   through friday schedule but this time you start  your fast at 10 am and then you end it at 6 pm   if you're up for an additional challenge you can  change up your fast day schedule to include the   weekend this works well if you find it hard to  control what you eat on the weekends but this is   not for everyone in this scenario you would have  an 8 hour eating window on monday wednesday friday   saturday and sunday and then you eat normally on  tuesday and thursday then in month number three   you can either do monday to friday schedule  or the alternative schedule i just explained   but now you want to decrease your eating window to  only six hours so for example eating from 11am to   5pm in your fourth month in onward you'll carry on  eating from 11am to 5pm but you're going to try to   do this every day this would be your ultimate  goal if these times don't make sense for your   individual needs feel free to change them up  for example as your end goal you may want to   start eating at 9 a.m and end at 3 p.m the timing  is up to you and what makes sense for your life   if you'd rather do intermittent fasting you  would still taper down one month at a time   but instead of tapering down the hours you would  taper down the calories with this method you're   going to either need a calorie controlled plan  done by someone like a registered dietitian   or you'll need a calorie counting app if calorie  counting is not for you you're probably just   better off doing time restricted eating now i'm  going to show you the five to two ratio diet the   goal here is that five days of the week you eat  normally and two days of the week you drastically   cut down calories for this way of eating you don't  have any time restrictions on any of those days   so you can eat your meals whenever you want but  my advice would be to eat during daylight hours   for the best health benefits the typical way  of getting here is that in your first month   you're going to eat normally for six days a  week and then on a predetermined day for example   monday you'll eat no more than 1 000 calories  in month 2 you're going to increase this to a   1 000 calorie day twice a week in other words  you're gonna eat normally for five days and then   calorie restrict on two of those days for example  monday and wednesday you're now at your goal for   fasting days and now we need to slowly bring down  the calories then on month three you reduce your   calories on monday and wednesday from 1000 to 750  calories per day and then in month four you reduce   it even further to 500 calories per day by the end  of month four you're eating normally for five days   and then you're eating no more than 500 calories  for two non-consecutive days it doesn't have to be   monday wednesday any two non-consecutive days will  work for example tuesday and thursday or wednesday   and friday etc you can use this exact method to  reduce your calories for alternate day fasting   the only difference would be that you include a  third low calorie day into the mix i'd recommend   you include this third day in month three all  you need to do now is to pick which type of   fasting suits you best and then get started  now to answer some frequently asked questions   first you might be wondering if fasting  will make you super hungry for too long   of course no one wants that some intermittent  fasting studies do show that leptin which is a   hunger hormone increases with fasting but these  same study participants did not indicate that   they subjectively felt hungrier so even though  their hunger hormone was higher they felt okay   generally speaking the first month  or so is the hardest but after that   people who do intermittent fasting don't have any  issues with feeling excessively hungry at the end   of the day how frequently you eat is a personal  decision that is influenced by a lot of factors   everyone's different if you find that you are able  to tolerate intervals of not eating or eating very   little then a fasting regimen may be the right  option for you next up because we all want results   like yesterday how long will it take for fasting  to work remember that when you fast your ketone   levels rise within the first eight to twelve hours  reaching levels between 0.2 to 0.5 millimolars   nutritional ketosis is experienced at levels over  0.5 millimolar so once you've fasted or eaten   very little for at least 12 hours you're going to  start reaping the benefits of metabolic switching   once you adopt the fasting diet give it a chance  to work it can take some time before you get used   to the side effects of fasting and having symptoms  like hunger irritability and loss of concentration   what the research tells us is that these types  of symptoms only last for two to four weeks   and that if you know what to expect then  sticking to the plan is much easier it's vital   to understand that your organ systems respond  to fasting by overcoming the challenge and then   restoring balance and that repeated exposure will  lead to a lasting adaptive response so even if   you try and fail trying is better than not ever  starting and finally is this something that you   can stick to most likely yes in a 2019 study that  compared three popular diets intermittent fasting   mediterranean diet and the paleo diet they found  that the dropout rates for intermittent fasting   and the mediterranean diet were much lower  compared with the paleo the authors concluded   that the more restricted the diet the more likely  it was that people would drop out for many people   included in this study intermittent fasting  was easy to incorporate into their everyday   lives and lots of them managed to follow it for  a longer period of time so let's take a look at   what the research is showing when it comes to the  three biggest health benefits of fasting health   benefit number one weight loss while maintaining  muscle mass if you eat enough protein this 12   week long trial found that normal and overweight  participants who underwent alternate day fasting   lost mainly fat and preserve their muscle mass  that's exactly what we want right another study   conducted on healthy young men found that those  who fasted for 16 hours per day on that 16 to 8   regimen lost fat but at the same time managed  to maintain their muscle mass this highlights   the importance of exercise while fasting on most  diets when you lose weight it's estimated that 25   of the weight loss is muscle mass which is not  what you want since more muscle mass means a   higher metabolism and a greater chance that you'll  get rid of the fat more often than not fasting   leads to reduced energy intake and subsequently  reduced protein intake we need to be careful when   this happens because fasting can be a fantastic  way to lose weight and maintain muscle mass but   only if you include strength exercises and eat  enough protein this is one of the reasons why the   elderly who are at risk of sarcopenia of aging  meaning age-related muscle loss they have to be   careful fasting without proper medical supervision  and support health benefit number two is that   fasting can improve insulin sensitivity a number  of studies conducted on different populations over   varying periods of time has shown that fasting  has the potential to improve insulin sensitivity   the more sensitive the cells are to insulin the  less insulin the body needs to produce to help   you digest and absorb your food especially when it  comes to carbohydrates having lower insulin levels   is a sign of good metabolic health and reduces the  risk for diabetes and lower levels of insulin may   also help with weight loss as they are related  those who routinely incorporate fasting in their   lives seem to also have fewer cases of diabetes  for example in okinawa japan we see that fasting   in addition to choosing low energy but nutrient  dense foods can result in a population with low   rates of obesity and diabetes as well as extreme  longevity examples of these foods include okinawan   sweet potatoes legumes and other vegetables to  back these observational studies up even further   members of the calorie restriction society who  follow the cron diet the calorie restriction with   optimal nutrition they have low rates of diabetes  and lower levels of hormones that are associated   with diabetes they had low levels of growth  hormone and insulin like growth factor one as well   as lower markers of inflammation and oxidative  stress when you add it all up it looks more and   more that there's a credible case to be made that  fasting plays a large part in preventing diabetes   health benefit number three possible improvements  in brain health some studies in humans show that   fasting enhances mental cognition especially  when it comes to memory for example a clinical   trial studied a group of older adults who were  about 60 years old and found that a short-term   regimen of caloric restriction specifically  a 30 restriction improved their verbal memory   these results are possibly due to higher synaptic  plasticity in the brain because of improved   insulin sensitivity and reduced inflammatory  activity basically the synapses between neurons   in the brain are strengthened leading to positive  outcomes in better brain health weight loss in   and of itself can also lead to better brain  health fasting may also have an effect on   the prevention and progression of a variety of  neurological diseases this is where the research   really starts to get interesting neurodegenerative  disorders are diseases of the brain that lead to   cognitive decline that gets worse as time moves on  we're talking about diseases here like alzheimer's   other types of dementia and parkinson's disease  one hypothesis is that some of these disorders   are caused by an excessive intake of energy  particularly in midlife so in these cases   fasting as a preventative method starts to make  sense because part of the regimen is to reduce   the amount of energy that you consume while these  studies are still in their infancy there are some   promising results some of the preliminary benefits  include seizure control and epilepsy prevention of   and improved cognitive function in alzheimer's  disease as well as some improvements in mood and   anxiety while all this sounds great these studies  are not definitive so still lots to learn here   another possible health benefit of fasting is its  potential to prevent or slow down the progression   of certain types of cancers cancer is a very  complex group of diseases and while nutrition   definitely cannot cure cancer a number of studies  and animals have shown that various forms of   fasting can decrease the likelihood of some  cancers developing for example in some studies   fasting decreased the formation of spontaneous  tumors in rodents which is part of the normal   aging process of rodents fasting may also be able  to suppress the growth of some types of tumors   and increase the rodent's sensitivity to cancer  treatment like radiation and chemotherapy it's   thought that fasting interferes with the way that  the cancer cell grows and makes it weaker which is   good because then the cancer drugs can destroy  more easily there have been a few case studies   that have shown promise with fasting in humans  with specific types of cancers like glioblastoma   which is a quite aggressive cancer that usually  occurs in the brain or spinal cord some case   studies suggested that fasting can suppress  tumor growth and help people live a little longer   so fasting research is ongoing in a variety of  disease states and is looking promising a number   of clinical trials are underway to assess how  fasting affects multiple diseases like asthma   multiple sclerosis arthritis and other forms  of cancer including breast ovarian prostate   endometrial and colorectal okay on to part five  fasting for weight loss did you know that it's   been predicted that by the year 2030 more than  half of the u.s population will be classified as   obese and this doesn't even account for the number  of people who are classified as overweight if you   think fasting could be a good fit for you that's  great because it has tremendous potential to help   you lose fat a review article that was conducted  in 2020 looked at 27 trials where participants   took part in some form of fasting they found  that fasting resulted in weight loss between   0.8 to 13 percent from baseline body weight and  waist circumference also decreased this systemic   review of 40 studies found that participants who  did intermittent fasting typically lost 7 to 11   pounds over a period of 10 weeks however a brand  new meta-analysis done in 2021 showed that not all   fasting methods are equal when it comes to weight  loss it highlights the 5 to 2 intermittent fasting   diet and the modified alternate day fasting to  madf as being the ones that are most closely   associated with successful weight loss remember  that both the five to two and madf encourage that   you eat between zero to forty percent of your  usual intake on the fasting days with five to   two you'll fast on two non-consecutive days and  with the madf you'll fast every other day for   at least three to five days out of the week it  wasn't surprising that in general it was found   that combining exercise with fasting drastically  improved the weight loss with one study showing   that weight loss doubled when exercise was added  spoiler alert at the moment the research is   showing us that weight loss when fasting versus  normal calorie restriction is roughly the same   as with any other diet research backed or not if  you are in a calorie deficit you'll probably lose   weight in most cases the dropout rate between  calorie restriction and fasting also seems to   be the same but when you're on a low calorie diet  for a long period of time physiological changes   can occur that cause your body to adapt to the  calorie restriction essentially your body gets   used to being on a low calorie diet and the  pounds come off at a slower rate intermittent   fasting addresses this problem by cycling between  low caloric intake for a period of time followed   by normal eating it tries to switch things up and  keep the body guessing while we think that this   may help on a physiological level we still need  more studies where it does seem to help though is   from a compliance point of view most weight loss  diets backfire because people give up it becomes   boring and too hard but with fasting there's a  bit more flexibility and food freedom fasting   by itself is not necessarily a superior weight  loss diet just a different way of doing things   fasting as with almost every other diet is the  most successful at the beginning usually the first   six months after that most people end up hitting a  plateau and this is common when losing weight and   the best thing to do is to stick to your plan and  focus on fueling your body with healthy food and   of course exercise if you're worried that fasting  may have adverse effects the same review article   showed that no adverse effects were reported in  all 27 trials now there were some fasting related   effects like altered mood but as i mentioned  before if you're aware of the expected effects   then you can mentally prepare and better handle  them especially when you know that the research   tells us that these side effects are self-limiting  and will probably go away between two weeks and   one month although fasting and traditional calorie  restrictions seem to have similar results with   regards to weight loss in the short term less  than two years what will be interesting is the   combination of fasting techniques with a healthy  dietary pattern one of the problems we have with   the research that's been conducted on fasting  so far is that many of the studies don't help   people choose what foods to eat how much to eat or  encourage healthy lifestyle changes like exercise   or improve sleeping habits i think that once the  research catches up and incorporates these we may   start to see some pretty great weight loss results  so what should you be eating when undertaking any   of these fasting regimens many of the fasting  studies conducted in recent years have not   controlled for the types of foods that people eat  they only focused on when people ate or didn't eat   while the fed in the fastened states may provide  your body with metabolic advantages and may also   result in weight loss what you eat is as important  as when you eat pairing fasting with a healthy   diet like the mediterranean diet may be the key to  cracking the obesity code on a long term basis the   american dietary guidelines for 2020 to 2025 have  been developed by experts and policy makers across   the country essentially they are a set of dietary  recommendations that are updated every five years   when we summarize the high quality evidence  available to us in these guidelines as well as   in consensus statements and high quality studies  we can see that a healthy diet or healthy dietary   patterns are made up of the following components  eat plenty of whole fruits and vegetables of all   types especially aiming for more vegetables than  fruit eat high fiber starches and choose mainly   whole grains eat protein-containing foods daily  from a variety of sources so vegetarian vegan   animal products that are lean meats that's  what's great choose minimally processed fats   and oils from plant sources some of us are visual  learners so using a tool like the harvard healthy   eating plate can help you understand what these  recommendations look like on a meal per meal basis   using a plate model is an example of a food-based  approach this is a good way of looking at   nutrition because that's what we eat food now this  is in contrast to past dietary recommendations   that focused on single nutrients many of you  may have heard of counting your macros or   macronutrients the macronutrients include protein  fat and carbohydrates the nutrients that have   commonly been demonized include fat especially  in the 90s and more recently carbohydrates   carbs but remember we don't eat these nutrients in  isolation and the meals we eat are a combination   of all three macronutrients so it doesn't make  sense to focus on one or the other a significant   portion of research shows that there is no ideal  macronutrient distribution and that we should   rather focus on choosing high quality minimally  processed or unprocessed foods and minimizing   low quality foods or ultra processed foods upfs  this includes foods with added sugar in the   back of your mind i want you to think about the  kinds of foods that you regularly eat what does   that food look like can you more or less see or  imagine what the unprocessed or natural version   of that food looked like when it was harvested  at the farm these kinds of foods the ones where   you can visualize the natural food are known as  unprocessed or minimally processed foods sometimes   they've been altered to make preparing the food  a little easier or to make eating that food a   little safer two good examples of this are rolled  oats and pasteurized milk when oats are harvested   they look very similar to wheat and are known  as oat berries cooking oats from this state   takes a very long time so what manufacturers  have done is streamed and rolled the oats to   make them quicker to cook this is a form of  processing but rolled oats are considered   to be minimally processed when you look at the  list of ingredients in your box of rolled oats   the only ingredients should be oats the more the  oats are rolled steamed and cut up the quicker   it will cook and this is the difference between  rolled oats and old-fashioned notes and quick   cooking notes pasteurized milk is pretty much  exactly the same as when it's milked from the cow   but it has been heated to a high temperature or  pasteurized to make it safer for us to consume   pasteurization kills the harmful bacteria that  might otherwise make us ill once again if you   look at the label of your milk the only ingredient  should be milk when we cook we often use things   like sugar salt and oil these products are called  culinary ingredients and most are also considered   to be minimally processed they've been created  using a variety of methods like pressing refining   extracting or mining and are used to prepare  and season our whole and minimally processed   foods some oils are the exception to this  rule as they have been highly refined like   canola and sunflower oil manufacturers can also  combine minimally processed foods with sugar   salt or oil to either increase their shelf life  enable self-storage or make it easier to prepare   think of foods that have been canned or bottled  with or without salt added or sugar added bread   cheeses and vegetables like sauerkraut that have  been produced using non-alcoholic fermentation   if we avoided these processing methods we would  either eliminate a variety of foods from our diet   because they would just be too tedious to prepare  or we would literally be spending our lives in the   kitchen the foods that we need to steer clear  of are the ultra processed foods and ones with   added sugar these types of foods are hardly even  food anymore they're more like food-like products   often these food ingredients are combined in  ways that don't occur naturally to produce a   highly palatable and even addictive food-like  product foods like corn wheat soy cane and beet   or even ground up animal carcasses are broken down  into single ingredients like sugar starches fiber   oil fats and protein some of these substances are  chemically modified through a variety of processes   like hydrolysis or hydrogenation and cosmetic  additives are added to make the final product   very tasty to eat these ingredients are then  assembled into their food-like form through   processes like extrusion molding and pre-frying  these so-called foods are then packaged using   sophisticated methods to keep these ingredients  fresh and then sold to the consumer some good   examples include soft drinks sugar sweetened and  artificially sweetened hot dogs and cold cuts fast   food packaged cookies cakes and salty snacks these  are the foods you should be limiting in your diet   sadly more than half the food consumed in high  income countries like america is ultra processed   with middle and low income countries quickly  following soup upfs ultra processed foods   they contribute to glucose intolerance insulin  resistance and type 2 diabetes in two big ways   one they have an unbalanced nutritional profile  ingredients used to create upfs have been stripped   of all their natural nutrients especially vitamins  and minerals even when these nutrients are added   back they don't seem to have the same beneficial  effects on the body this is probably because   when we eat food real food all the nutrients work  together to improve our health these nutrient poor   upfs will usually displace the more nutritious  food items decreasing the overall quality of your   diet having a diet low in micronutrients  can increase your risk for deficiencies   and for chronic diseases they're also usually a  concentrated source of carbohydrates and sugars   and are also often low in protein and fiber this  means that all these sugars are absorbed quickly   each time your blood sugar rises what does your  pancreas do it secretes more insulin the more   sugar that you consume the more insulin is needed  eventually insulin resistance and subsequently   weight gain sets in the second thing they do is  that they promote over consumption so eating upfs   it leads to weight gain in one study the same  group of people were given a whole food diet   for two weeks where they could eat as much as  they wanted and this was followed by two weeks   of a diet containing upfs so when they ate the  upfs the participants ate more per day compared   to when they're eating the whole foods the real  food this highlights the addictive nature of these   foods and their inability to keep you feeling full  an invaluable skill to learn is how to spot upfs   we don't need to overanalyze everything we eat  because we know that fresh fruits and vegetables   including potatoes and the like are obviously not  ultra processed the same goes for pasteurized milk   and chilled meat cuts it becomes quite obvious  which foods are ultra processed when we look at   the ingredients listed on prepackaged goods if  you notice an ingredient in the list which is   never or very rarely used in the kitchen or is  considered to be a cosmetic additive then the   food item in question is probably ultra processed  so what should we be eating and what should we be   avoiding so in general you're going to want to  eat unprocessed or minimally processed foods   and avoid the ultra processed foods so who should  not do fasting because this diet is not suitable   for everyone there are primarily four groups  of people who should not fast and first up   is actively growing children or arguably any  children that are younger than the age of 18. why   for starters there's no research on fasting  diets in children and so from that point of view   we can't tell if it would be helpful or harmful  for their long-term health from a physiological   standpoint growing children need a significant  amount of energy to grow and they need a host   of other nutrients for proper development and to  prevent deficiencies if your child is overweight   a diet is not normally the answer quite often  kids pick up bad eating habits from their parents   or caregivers and this is the starting point for  change children thrive off regularity and having   regularly planned meals that contain a balance of  foods it's more about cutting out the bad foods   like the ultra processed foods and things with the  added sugar especially sugary drinks which is one   of the main sources of sugar in the american diet  this includes sodas and juices also maintaining   family meal times is also important number two  the next group that shouldn't fast is pregnant   or breastfeeding women remember that when you fast  you switch between using ketones when fasting and   glucose when eating animal experiments and  clinical studies have shown that exposure   to high ketone environment during pregnancy may  be related to poor maternal and infant outcomes   glucose is an important energy source for the  growing fetus and a shortage of it can affect the   growth and development of a number of the fetuses  organs including the brain this is also the reason   why women who are pregnant are not encouraged to  lose weight even if you are overweight in your   pregnancy the current recommendation is to rather  maintain your weight or minimize pregnancy weight   gain not to actively lose the weight in this time  frame number three fasting is also not recommended   for anyone who has a pattern of disordered  eating you may or may not have been diagnosed   with an eating disorder but if you find that you  become overly concerned or obsessed with what you   eat especially when you're on a diet then fasting  will probably trigger you and cause you to fixate   on food even more the behaviors will keep you  stuck in the binge diet cycle where you go from   being incredibly restricted to binging if you find  that you do this while on any diet it's important   to get help from a psychologist or registered  dietitian breaking away from the diet binge   cycle can be tough but with the right help it's  definitely doable last but not least number four   those who are older than the age of 70. as we  get older we eat less and start to lose muscle   mass this is known as sarcopenia of aging when you  fast you'll probably inadvertently take in fewer   calories and also less protein this may cause  unintended weight loss and further muscle loss   some of the research even points to the fact that  having a little extra weight may be beneficial for   this elderly population a meta-analysis done in  2014 actually found that a slightly higher bmi   was protective for all-cause mortality for older  adults now for the younger population the sweet   spot for health is between 19 and 25 but for older  adults the sweet spot was somewhere around 27 so   technically overweight they found that when older  people had a bmi of less than 23 or more than 37   their risk for mortality increased exponentially  what if you're someone with a medical condition   and you want to do fasting for medical reasons  now it can be done but under strict supervision   of your doctor and with regular monitoring  people with certain medical conditions don't   have to avoid fasting but should be careful and  consult a physician prior to doing so including   those who are taking any chronic medications so in  these cases the medication may need to be adjusted   especially if that medication needs to be  taken in conjunction with certain foods   the type of fasting regimen that you choose will  depend on your personal preferences and lifestyle   but the more we research the more obvious that  it is that eating during the daylight hours the   earlier the better seems to be ideal this means  aligning our eating with our circadian rhythm   to maximize the health benefits of fasting if you  decide to start either of these fasting regimens   the research shows that going slow in establishing  a habit is better the research is ongoing but one   of the biggest benefits of fasting is weight loss  this is what draws many people to the diet in the   first place when you restrict your eating window  or eat less on certain days you will take in fewer   calories and usually when this happens weight loss  is not that far behind fasting is an attractive   option for many people because it focuses mainly  on the timing rather than what you should eat   with that said the type of food that you put  in your mouth does matter so this means eating   real food and avoiding upfs especially those with  the added sugar besides weight loss fasting also   seems to be pretty healthy for most people and may  help to prevent or control a variety of chronic   diseases by means of a process called metabolic  switching which leads to improved metabolic health   including less inflammation in the body so  that's all thank you for watching this guide   on intermittent fasting in 2022 i hope you got a  lot out of it and i'll see you in the next video