Why do I feel like CRAP on low carbs?

It will take a while, but carbs are what fuels the brain - light headed, fatigue, headaches can occur from lack of carbs, not sure about the brain shutting off!

Actually, no. Carbohydrates are polysaccharides. Glucose, a monosaccharide, 'fuels' the brain. But the brain is not an obligatory glucose consumer so it easily makes the switch to relying on ketones which enter the same metabolic pathway as fatty acids. This saves the glucose for the obligatory users, like liver and skeletal muscle. Also, ketones can be used to produce glucose via GNG.

Carbohydrates are saccharides, "poly" just means how low the the chain is - glucose is a saccharide too...like I said it takes a while for the brain to shut down when there is a lack of glucose, but the primary source is glucose for the brain. I love my fruits and veggies and try to stay away from the processed breads and pastas...the veggies and fruits not only have carbs, but they have loads of vitamins and minerals.

What...the brain doesn't shut DOWN. It uses ketones! In the krebs cycle! To save glucose for the obligatory glucose users! How do you not know this?

I think the term "carbs" is over-used and oversimplified. When people talk about going "low carb" as a means of losing weight and getting healthier, I think they usually mean cutting out refined carbs, such as white sugar, white flour, white rice, etc. I honestly think that refined sugar and flour has no place in any healthy diet, so cutting THOSE out would definitely make a huge difference. But to lump all carbs together as "good" or "bad" doesn't make sense. All vegetables and fruits have carbohydrates and you should INCREASE your intake of those. Things like beans and legumes have carbohydrates, but also tons of fiber, protein, iron and other nutrients.

The fiber, vitamins, phytonutrients (and therefore a feeling of satiation and well-being) you get from fruit such as berries or citrus, could never be gotten from a piece of Wonder Bread. The breads, cakes, cookies, candy are simple carbs stripped of their fiber and loaded with sugar, with close to zero nutritional value.

That being said, you WILL feel like crap the first few days giving up these junky foods, because your body has probably developed an addiction to them! I know mine did...it was serious withdrawal symptoms, like trying to kick any other drug. But if you make sure you add lots of fresh unprocessed food to your diet, you will begin to feel amazing! Check out the Raw Family, http://www.rawfamily.com/. I suggest adding a "green smoothie" to your breakfast every day - you won't regret it!

"Carbs are essential to LIFE." Um, no. We may be addicted to them when they come in grain form ("healthy whole grain" is like saying "healthy filtered cigarettes", neither is healthy, just a less unhealthy option) Carbs are a great source of vitamins when wrapped up in veggies and LIMITED fruits, they suck and are unhealthy when they come from grains. People just don't want to give up their sugar. I can relate but I do my sugar more often straight up instead of pretending grains are anything else.

Your body can convert fats and proteins into the same things carbs give you.

Those "healthy whole grains?" They have to have B vitamins ADDED for nutrition, that doesn't come naturally. I get so tired of the misinformation regarding carbs. People are so addicted (hey, been there, done that and have fallen off the wagon more than once) they will exercise for HOURS trying to do what eating right will do naturally. Exercise for health and fitness, not for calorie burning. Eat calories in the right form (NOT grains) and you will be able to exercise much less. It's no less sustainable as trying to burn off those calories in a never ending ratrace . You have to give up something, either you give up the excess carbs or you give up calories elsewhere (fats and proteins which are what you were designed to live on) and/or hours and hours of mindnumbing cardio.

Ha, the irony, tired of misinformation, and spouting misinformation. Classic.

I eat high protein low carbs and haven`t noticed any crap days.

Some carbs are good I havent got a problem with them..I just find high protein helps me lose weight and makes me feel better.

Serotonin (happy hormone) has nothing at all to do with low carb diets.....take this from a psychologist!!!

High protein feeds muscles etc etc lots of threads on this.

Eating clean is more the way to go no processed foods

editing to add eat fat too!!!

Dr. Daniel Amen, psychiatrist, disagrees. Seratonin levels are affected by what you eat, but it varies from person to person. He does brain SPECT scans (about 150,000 to date) and extensive research on how dieting and other lifestyle factors affect the brain. His conclusion is that not every brain is wired the same way. Some people feel better on more protein, and some feel better on more carbs. If you're on the right diet for your particular brain type, you'll lose weight faster, and feel better in the process. His book "The Amen Solution" has more on this. Sorry to sound like an advertisement, but I'm very impressed with his work!

Dr. Daniel Amen, psychiatrist, disagrees. Seratonin levels are affected by what you eat, but it varies from person to person. He does brain SPECT scans (about 150,000 to date) and extensive research on how dieting and other lifestyle factors affect the brain. His conclusion is that not every brain is wired the same way. Some people feel better on more protein, and some feel better on more carbs. If you're on the right diet for your particular brain type, you'll lose weight faster, and feel better in the process. His book "The Amen Solution" has more on this. Sorry to sound like an advertisement, but I'm very impressed with his work!

I don't know of Dr. Amen... but I also think food effects serotonin levels, albeit in an indirect manner. I don't think it's limited to carbs... and it wouldn't surprise me at all that people respond differently to different types of food. Food DOES activate 'reward' pathways in our brain... it's part of our biology, but it's also a result of training. From the time we were infants, many of us have been using food to 'sooth' and 'comfort' (bottle for crying baby anyone?), so naturally different foods will trigger serotonin (and dopamine) release. If we're raised on a high carb diet, it might be carbs that trigger the greatest response. I don't know... I'm speculating on all this... but it makes sense to me.

Your BRAIN does. NO carbs can cause neurological shut down.

I suppose it's lucky that even those on super low carb diets aren't on the zero carb diet. Or are you mistaking very low carb for zero carb?

So... is a low carb diet (50-100g carbs a day) sustainable for life? I see that diabetics find it useful so shouldn't it be safe for non-diabetics?

Carbs are essential to LIFE. You can "lose weight" eating ANYTHING, as long as your expenditure of energy is less than your consumption. You could go on the "chocolate bar diet" and lose weight as long as the calories you consume are less than what you put out. I'm not talking about just weight loss. If you want a healthy body, you need carbs. You need protein. You need more carbs than protein.

Wow - Imagine the poor Inuit people - apparently they did not get the memo.

Just like every time the Govt wants to re-do the "food pyramid," All the lobby groups come out with their money to make sure that they are well represented on the "new food pyramid" so that we can use words like "well balanced" in a "can't we all get along" thinking plan of eating. Just make sure you include this food group in your DAILY eating (so we make a lot of money after we brain wash the masses.)

<<<<<<<<<<<<<<<<<<<look at me, I eat anywhere between 150 and 200 carbs a day.

Its called balance people. We should not deprive our bodies of nutrients, we should not fear food, that is just plain sad. We need carbs for energy, oh yes we do.

When we live a healthy happy life, we eat a good variety of good foods and feel GREAT!

@lesasass

Try needing to lose 100 pounds. A person gets mighty impatient. Not saying it's the best way, but there's a big difference in needing to lose 5 pounds or.. mega pounds.

Just because I look great today does not mean I always did. I have lost 40 over 4.5 years. I have done it with a pair of shoes and a fork. I can not speak to needing to lose 100 lbs, but this is a life long journey in eating correctly and living right, not a fast way to lose weight. Do not forget that the faster you lose that much weight, the greater the chance there is that you will have sagging skin, which is not attractive at all.

You can do what you want to do, it really is your business. When I got here I needed to lose those last few lbs that a 43 year old would love to lose, and I did it. I did not start in January when I signed up for this site. I started in September of 2007. So for me, being patient has paid off, big time.

Balance is the key to EVERYTHING in life. I strive, every day, for balance of mind, body and spirit. This is the way I live, after all, this is the only life I have, I am going to enjoy it.

Most of us who endeavor to lose a lot of weight do not speak in a condescending manner. Oh, no we don't people. Just because we are still struggling doesn't mean we are stupid. Congrats on losing weight.

IF you took my manner of speaking as condescending, that is your issue, not mine because I was in no way shape or form trying to be.

I started this road to well being with trying to get my mind healthy first. Why was I doing the things I was doing to make me so over weight and unhealthy? After I found out why I was being so destructive,got to work on my spirit then I started on the body portion of my journey. Maybe I would have taken someones comments that were not meant to be hurtful as hurtful back then, because I was powerless and my life was totally unmanageable. Today I make the choice of what I allow to get to me and what I do not. This is the basis behind making better choices, because I do not allow another persons thoughts or feelings toward me dictate what I do to my body.

I honestly hope you find the path that is the right one for you that will make you not only fit, but happy, in all three, mind, body and spirit.

Good carbs are fine, but prolonged low carb diets will make you moody, irritable and if training/exercising too you will feel tired.

Do you have any studies to back this up? I am neither moody or irritable, happier than I have ever been and better able to deal with stress than I could have when I was 174lbs heavier, I train heavily and I am not tired, have energy enough to run circles around my teenage boys and their friends.

I do not have scientific quotes/links to throw at you and letters after my name like some others in this thread, and fair play to them, but i have been in the fitness game for 25 years and have encountered lots of different types of exercise, sports etc during this period. I have my own groups/classes and do PT too, and i have seen many many people over the years try different fad diets and all the other 'diets' out there (i hate the word 'diet'!) ... but my point is that every time (well almost) someone in my classes/groups etc has 'tried' the low carb plan they have expressed tiredness and irritability, sometimes noticeable in a tough class. Normally within the first 5 days, and i know some say that after a week it gets easier/better, but by then most have quit the plan because the craving for carbs is too much or they think they cant continue.

Yes i know everyones different and the metabolisms vary and the way their body functions may vary but on the whole in my experience MOST people do not train/exercise well on low carb 'diets'. If you can then you are in the minority in my experience, should i use the word 'lucky'? ... someone on this thread said something along the lines of 'we are all different and react different and all the rest, this i believe is true, broad 'facts' dont cover everyone. My father for instance, eats whatever he likes, including what most people would call 'junk' and has never budged in his weight? He doesnt exercise either, how is that?

We talk about higher metabolisms etc and improving your metabolic rate through training, can one of you with the scientific expertise to back it up explain this to me... i hate my Dad, i want to eat like him and never have to worry! :laugh:

We should all do what works for US... but in the end if you 'eat healthily' and exercise regularly you wont go far wrong! .. i have always 'fed' on good Carbs and i dont think ive done too badly?!

I can only speak from personal experience but I ate 50-120g carbs a day for about 2 months, with a calorie intake of maybe 1200cals. The latter I didn't realise I was doing until I recorded it on MFP and have since increased my intake as it is not in tune with my fitness goals. Initially, I was tired and my breath tasted funny. I didn't have issues with being hungry (just ate more protein if I felt hungry) plus I was eating more frequently.

I didn't notice any decrease in my ability to judge risk (I am involved daily in financial risk, I climb and I lift heavy weights - no adverse outcomes have been experienced in any of these arenas), critical thinking (in fact, I might even suggest it sharpened my ability to tear apart someone's argument) nor perform physical activities (I had increased my cardio work for a start).

My "addiction" to carbs has proven to be non-existent. I used to eat 8-10 25g bags of crisps a day about two years ago, reduced it to 1-2 six months ago through choice although did creep up to 3 bags occasionally... now 1 or 2 a week after weights for salt and carb reasons. Yes, bad carbs, so what? I wonder if we have an "addiction" simply because we feel compelled to eat carbs with meat and vegetables as our parents taught us to. It feels naughty to just eat a lump of meat on its own.

I am not sure where I am going with this post but just thought it was an interesting experience especially for those looking to lose weight (which I did).

*Also, i need to qualify 'glucose is the only source' with 'relatively readily available'. plus, as songbyrd says, glucose is made from ketones. i don't know if the ketones themselves cross to the brain or if the glucose needs to be constructed first - songbyrd will know.

You've activated my nerd button. I'm gonna have to find out if ketones cross the blood brain barrier. I'm pretty sure they do, but I'm not 100% positive. It's possible the astrocytes make ketones from some precursor molecule that crosses. I will find out for sure, just because I'm curious.

Ketones are made into glucose in the liver. It's the only site of gluconeogenesis. Ketones can be converted to Krebs cycle intermediates.

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Obviously because your body DEPENDS on GLUCOSE! The brains only runs on glucose not bloody protein like you low carbers seem to think. Carbs aren't the devil. People are just so uneducated these days.

I don't understand the 'low carb' diet thing.

I agree, people eat too much white enriched crap. Get that out of your diet - I will COMPLETELY support that.

However, fruits and veggies have carbs. If I eat 4 celery stalks, 1 carrot and 1 apple in a day (those are my snacks for next week) that is 44 carbs right there. No one can tell me that my fruits and veggies are bad for me. Also, I dont see the problem with whole grains in the forms of multigrain/multiseeds breads, whole wheat pasta, wheat cous cous - Etc.

I think a lot of people have the wrong idea -=shurgs=- I also do not believe it is sustainable in anyway.

Totally agree with this! Carbs are NOT evil. Make sure you're taking in the right kind of carbs, complex carbs. They comes from fruits, vegetables, yogurt, quinoa... These carbs are good. The evil/bad carbs are refined carbs! White rice, white bread, pasta, sugary breakfast cereals... Too much of these carbs will cause weight gain.

Bottomline: Avoid refined carbs and get your carbs in the right places!