Oatmeal Diet

 By Mizpah Matus B.Hlth.Sc(Hons)

oatmeal-dietThe basic Oatmeal Diet involves replacing one or two meals a day with oatmeal.

This is good since oatmeal has a number of health benefits including

  • healthy weight management
  • reducing cholesterol
  • and potentially lowering the risk of certain types of cancer.

Some have taken this further by eating nothing but oatmeal. This approach is a tad extreme, but most people follow the version listed below.

Oatmeal Diet Basics

One method of doing the oatmeal diet involves varying the amount of oatmeal eaten over three phases.

Phase One

  • Dieters eat nothing but oatmeal for the first week.
  • You can eat ½ cup of oatmeal for each meal, which may be combined with ½ cup of skim milk if desired.
  • Only whole oatmeal is allowed.
  • Instant oatmeal and granola bars should be avoided for the first seven days.
  • Calorie consumption for the first seven days should be between 900-1200 calories per day.

Phase Two

  • For the next 30 days dieters continue having ½ cup of oatmeal three times a day in addition to their regular diet.
  • Instant oatmeal is now permitted.
  • Calories may now be increased slightly to 1000-1300 per day.
  • A morning snack of ½ cup of fruit and an afternoon snack of ½ cup raw vegetables are allowed.

Phase Three

  • After 30 days you may begin to eat your normal diet while continuing with one meal and one snack of oatmeal daily.
  • Dieters are advised to limit their intake of fats when returning to normal eating.

The biggest challenge to eating oatmeal (also known as porridge in the UK) is how to keep adding things to prevent monotony and blandness. See some ideas here.

Oatmeal Diet Alternatives

  1. Medifast- Uses meal replacements like oatmeal and shakes to promote weight loss.
  2. Special K Diet- Replaces 2 meals a day with Special K Cereal.
  3. SlimFast- Uses meal replacement shakes and bars instead of oatmeal.
  4. Cooking with Oats: Oat Bran, Oatmeal, and More

Oatmeal Recipe Ideas

Recommended Foods

Oatmeal, skim milk, berries, bananas, apples, oranges, grapes, carrots, red pepper, celery, lettuce, spinach, chicken breast, fish, coffee, tea, club soda, sugar free pudding.

Sample 1 Day Meal Plan

4 more days of the oatmeal diet meal plan can be found here.


½ cup oatmeal
½ cup skim milk
1 tablespoon raisins
½ teaspoon cinnamon
coffee or tea

Morning Snack

½ cup blueberries

Lunch½ cup oatmeal
1/2 cup low fat yogurt
1 banana
Afternoon Snack

½ cup raw vegetable sticks


4 oz grilled chicken breast
Large green salad
½ cup oatmeal

Evening Snack

Sugar free pudding

Exercise Recommendations

30 minutes of exercise is recommended on 3-5 days of the week.

Costs and Expenses

The only cost for this diet is for groceries, which will probably be even less than usual because oatmeal is very inexpensive.

The oatmeal diet is similar to other Meal Replacement Diets


  • Oatmeal is high in soluble fiber, which helps to promote a feeling of fullness after meals.
  • A diet high in oatmeal can reduce the ‘bad’ LDL cholesterol without affecting the ‘good’ HDL cholesterol and has been demonstrated to be as effective as cholesterol lowering medication.
  • Oatmeal is a good source of low glycemic carbohydrates and can help to promote stable blood sugar levels.
  • Oats contain phytonutrients called lignans, which are beneficial for heart health.
  • Oats are very inexpensive.


  • Calorie intakes are below that recommended for safe and healthy weight loss.
  • Lack of variety in the diet will limit the ability to obtain adequate nutrition.
  • Diet involves a dramatic change in normal eating patterns, especially for the first week, which has the potential to trigger yo-yo dieting for some people.

The First 7 Days May be Difficult

Any diet that is based on a single food while excluding other healthy foods can be regarded as a fad diet that will not be supportive of the health of the dieter. It is not recommended to follow the first seven days of the version of the diet where oatmeal is the only food permitted.

However, the oatmeal diet is based on a nutritious food that can help to reduce appetite, which makes it a good source of carbohydrates for a weight loss diet. If weight loss is to be maintained over the long term it will also be necessary to pay attention to other aspects of nutrition and lifestyle.

 By Mizpah Matus B.Hlth.Sc(Hons)
  • Pingback: Healthy Diet Oatmeal – about food and health

  • Shannon Summers

    I lost 60lb on this diet over two years ago going from a size 12 /14 to a 0/2.

    • Romo

      How strict where you on the diet? Did you exercise? And how long did it take you?

      • Shannon Summers

        For the first 10 days I ate Snoqualmie Falls Oatmeal for 3 meals a day. I try to limit what I put in my oatmeal to under 100 calories. After that for the next 20 days I ate Oatmeal for 2 times a day with no more than 100 calories added and a healthy 3rd meal under 400 calories. In the first 30 days I lost 20lb. By the end of the year I lost an additional 30lb by eating 1 to 2 Oatmeal meals a day with 1 to 2 low calorie meals a day. The last 10 was the hardest to lose for a total of 60 lbs.

        I did not exercise until about 3 months into my diet. Then I when to the gym for the next year 3 times a week for an hour each time. 50% cardio 50% weights. Eventualy I moved to making it to the Gym 5 days a week. To get more out of your workouts try moving back and forth between cardio and weights. I do 10 minutes of cardio and then 10 minutes weights.

        Now I make healthy meal decisions, try to eat oatmeal at least once a day and if I find I gain a pound or so I just eat oatmeal until it comes off. I look and feel great now and can wear whatever I like. The only two down
        sides I have found to the diet are it is hard to wing yourself off the oatmeal. I don’t feel good if I don’t have at least one bowl a day. The other downside
        is I am always cold. My husband says it is because I have no fat on me.

        I am 38 and was 35 when I began this. My biggest motivation when my family was eating bad things was to go stand on the scale and see how much I had lost. This diet is not for everyone but it sure worked for me. I think I could write a book on all the ways to make oatmeal.

      • Romo

        Wow, First off thank you for Responding. And second congrats on your weight loss. You have inspired me to do it and stick with it. I’ve have been hesitant and start but then fall off the Wagon. But your story only motivates to start and stick with it. Thanks :)

      • Shannon Summers

        Good luck and keep me posted on how you do.

      • China

        I enjoyed reading your weightloss story. I’m sure you have inspired others who are in need to lose weight such as myself! I have 2 questions: did you use milk or water with your oatmeal? secondly; did you have a cheat day.. weekly or monthly or not at all? thanks!

      • Shannon Summers

        I did not use milk or butter in my oatmeal. I also do not eat instant. That being said most non-instant oatmeal can be made from hot water from the water cooler or ordering a cup of hot water and a banana from Starbucks. Some of my favorite oatmeal combinations are: (almond sliver, cranberries and coconut flakes), (spoon of peanut butter or Nutella), (cinnamon and raisons). You can put whatever you want in it as long as it is less than 100 calories. I have found that chocolate protein shake mix does not work well.

        I did not have cheat days but I did have a philosophy. There are times you are going to have a higher calorie meal. That is ok sometimes.
        • After the 30 days, know how many calories you are eating if it is a higher calorie meal.
        • There are many times I have taken a bite of something and decided that is was not worth the calorie and did not finish it.
        • Just because you have had a high calorie meal does not mean you throughout the day as a high calorie day or week.
        • There is no making up for calories eaten by skipping meals the next day. I did offset them by spending more time at the gym.
        • Don’t beat yourself up over birthday cake just make sure it is worth it

      • China

        Thank you for the response. I’m ready to do this, i begin the oatmeal diet tomorrow. I hope to be within my goal in 3 months from today.

  • mae

    Hi. Good day to all:-) I want to try oatmeal for breakfast this month.. it’s hard to say that other people insult me that i ‘m a fat woman I’m 22 and my weigth is 71.8kls plz help me:-)

  • Gigi

    I put honey and pepper in my oatmeal. So yummy

  • Sam

    Hi Guys
    Any updates on the progress so far …I am starting this today .

  • Phil

    Eating oatmeal can be tasty! The problem with oatmeal is that it has been lumped into the breakfast cereal catagory and we associate sugar, fruit, milk with oatmeal.
    In reality, oatmeal can take on any flavor since it is neutral and mostly fiber.
    Here is a example recipe I make in the microwave every morn. Since I’m not a sweet person, I prefer savory flavors on the salty side.
    Step one. Add to one cup of water, half cup of chopped broccoli (or fleurettes), teaspoon of chicken bouillon, dry. ( you can also add, curry powder, sage or celery seeds at the stage for a variety of flavors.)
    Step two. Microwave for two minutes in a a large pyrex measuring cup.
    Add 1/2 cup dry oatmeal and mix. Microwave for additional two minutes.
    A wonderful lunch, breakfast, dinner and less than 220 calories.

  • Debra

    Don’t know if you will get this but I too have about. 70 pounds to lose how long will it take eating oatmeal three times a day an doing 30 minutes a day on the treadmill ? Debbie

    • Ian

      Best of luck. Have you looked into the Dukan Diet. I would recommend it, but beware if you fall off the diet and put weight back on, dieting/weight loss is so much harder.

  • Melissa

    Am 5.1 and 195lbs I am going to start doing this diet I really want to lose weight. I am a size 14 and I want to be a size 8 all my fat is round my belly.wish me luck :D

    • cc

      GOOD LUCK!

  • Randi

    I think starting tomorrow I am going to try this I LOVE oatmeal in all forms both stovetop and baked sweet or savory this also looks like one of the less expensive diets out there

    • Brodin

      you’ll hate it after 1 month, in all forms except raw.

  • Listey

    I lost over 5 lbs in a week just eating oatmeal a couple nights a week in the past. I can imagine how much weight I can lose eating it every day X 2 times a day. Not only will you lose weight but your bad cholesterol will decrease and your good cholesterol will increase. I am 208 lbs now and 5 10 female and my oatmeal challenge begins in the morning. For those of you with children that need ‘real’ food. Cook just enough for them, extra veggies are always good though and this way you wont find yourself pigging out on the family dinner.

    I will check back each week with an update. I would like to lose the weight in a healthy manner so I am not looking for the weight to come off immediately. Slow and steady is the best. I will keep all updated.

    • SusanQuagmire

      Listey – not sure if you’ll see this but I’m also your height (female) and I weigh 214 lbs. I’m wondering if you did this diet and if you were successful? I’m thinking of adding some protein powder to the oatmeal to get more protein. Please update me if you get this…thank you!! ; )

    • joyce

      Hi I’m a 154 pounds and I’m only 17 years old, how can I lose weight fast? Can eating oatmeal help me? Thank you :)

  • Adi

    Hi everyone! I’m 5ft1 and 99 pounds. I’d like to just trim down – maybe 5 to 10 pounds. Gonna go on a light 1 week oatmeal diet. Good luck to all! :)

    • Ry

      Adi Ur kidding right? 99 pounds Ur definitely underweight. U should not trim down u should be gaining weight. Sorry but it’s the truth

  • Sweden

    Oatmeal 3 times a day and fruits and water in between. I lost 20 punds/ 10 kg in 2 months! Good luck to you all * * *

  • Alexa

    I am starting tomorrow ( 160) I wanna lose 30 before summer. I exercise everyday but cause eat sooo much there is no weight loss . Hopefully oatmeal diet will help me

  • Ireneeee

    Day 2.. Oatmeal for both breakfast and lunch, I had almonds for a snack. For dinner, baked chicken wings (2), broccoli, and mac n cheese. I weighed in this morning at 166 lbs.. I did about 50 mins of low impact cardio…#feelinggood.

  • Ireneeee

    Here goes.. Day 1,, I ate 1 package of instant oatmeal (original), with a tbsp of sugar, I had this for both breakfast and lunch .. coffee and water to drink only.. for dinner I ate a can of tuna fish with cabbage.. yum :) I did about 30 mins of low impact cardio… stay tuned!

  • Mary

    Is it
    1/2 cup dry oats = 1cup cooked or
    1/4 cup dry = 1/2 cooked.

    • Gus

      Mary, I measure a 1/2 cup of oatmeal and mix it with water or skim milk…..and I get a pretty satisfying and filling meal out of it…but to answer you question, on my container of oats it says 1/2 of oats makes 1 cup of prepared (cooked) oats…and that what I use….hope it helps

  • Mike Heil

    I eat 1/2 cup oats with 2 tbsp of peanut butter

  • Katrina Mae B. Mangsat

    I am about to start my oatmeal diet.

  • Glenn Swanson

    Hi im 26 6ft 3in and just shy of 20 stone i lost weight last year but gained it again so i want to try rid it for good. What way would this oatmeal diet affect me if i ate nothing but oatmeal for 3 weeks with fresh fruit and lots of water plys some fresh vegetables plus hiking every morning 260 feet for exercise. All feedback would be greatly appritiated.

  • janie mendiola

    Hello I just wanted to know can you add splenda to your oat meal

    • nicole

      Janie, Have you tried agave nectar? Its an all natural sweetener thats so much healthier than sugar or honey and in my opinion much sweeter! I just switched and I love it. You can get it at any store but I get mine from costco since its such a steal compared to other stores =]

    • James

      Enjoy cancer.

      Splenda and other artificial sweeteners are well proven to cause cancer.

      • Hannah

        You can get cancer from almost everything. So enjoy cancer yourself.

      • http://www.everydiet.org ted

        Could you list some studies that prove this statement?

    • http://www.everydiet.org ted

      yes, But stevia or xylitol would be better since they are natural.

  • debi

    I am considering doing this diet for the next 3mths. I am considerably overweight and desperately wanting to get this weight off. I was wondering if I decided to go with oatmeal diet can I take protein shakes? And will these protein shakes compromise my diet ( make me gain weight )? And if not please suggest a name of protein to use.

    • JB

      I did not follow this exact oatmeal diet, as a mater of fact I never knew it existed until today; however, I did eat oatmeal for breakfast and lunch with an apple as a snack in between, and a healthy dinner (normally a chef salad, or veggie wrap, or veggie burger) and I lost over 20 pounds in less than two months. Best all time recipe is to make your oats, either whole oats or from a oatmeal packet, cut up an apple in small bites, add cinnamon, and cook in the microwave- and it’s like eating a yummy apple crisp dessert!

    • James

      Instead or protein shakes which are generally just garbage, buy yourself minerals and vitamins at the local walmart to make up for what you are losing with just an oatmeal diet. Eat fruits and vegetables, add some nuts, and you’ll be fine.

    • http://www.everydiet.org ted

      You should be able to use a low carb protein shake with this diet. Just avoid the ones high in sugar.

  • teedeegee

    i am a female weighing in at 210.2lbs. and i am 5’5″ This diet was recommended by a dominican doctor before i think about doing cosmetic surgery. I am going to try it today starting at lunch and i am very excited because i love oatmeal. I will keep you guys posted

    • Gus

      good luck teedeegee!!!!!! don’t give up and fight hard to get your results….you can do it!!!!!!!!!!

  • Ellie

    Started Sunday. Added fresh fruit and ground walnuts to the meal. My new friend…water. In the past, I only drank the stuff because my body needed it. Now…I can not believe how I eagerly down the bottled stuff!!

    My encouragement to each and every one of you dieters is take your time so the weight doesn’t come back and please exercise. It is so important. My mother walked all her life and it paid off. She is now 84 only one knee replacement surgery and no medication!

    Yes, she eats one bowl of oatmeal (except steel oats ugh) everyday!

  • Li

    Okej’ im 154 cm and 48.6 kg
    I wanna be 46. So i started today,will let you know if it works

  • Josie

    I plan to start this today. I love oatmeal, so I think this won’t be awful…however I do get hungry awfully fast. I am 5’4 and weigh at 118 pounds. I’m already thin, so I’m curious how effective this diet will be. I will continue to exercise moderately, every other day, and include vegetables and fruits in my diet. Does anyone know of a non-fat way to include protein into my diet, without having to buy protein powder?
    Best of luck to all my fellow oatmeal-diet friends!

  • Billy

    It works , I’ve known this secret for years Oatmeal and walking

  • Erin

    So I am on day 3 of phase 1 and I have lost approx 3lbs without exercise. I am gonna start my exercise program on phase 2 once eating the oatmeal becomes more like second nature. The gas is horrible however….So be prepared to toot alot….Anyway I use to have problems being regular and falling asleep, it seems this diet has fixed all that. I actually seem to need less sleep to function as well….added benefit I guess….So I will be updating y’all every so often….its always nice to read other peoples experiences…..Good luck Everyone!

    • Erin

      Correction day 5 of the diet ; )

    • Erin

      Okay so day four of the diet….and I have average about a lb of day of weight loss but yesterday I cheated and went on a chinese food bender….: ( …..So oatmeal peeps beware….the oatmeal diet does clean you out of toxins and if you cheat, you will feel like absolute crap….I slept for 14 hours after my chinese bender, and woke up this morning at 3am…..before my cheat my sleep improved greatly and I needed less probably because my body was detoxed, once I cheated my body was back to its old sluggish self…and I found myself having trouble falling asleep and oversleeping again…food coma to the max!! So today I am hitting the gym hard and going to cleanse before I get back on the plan…..wish me luck!!

  • Judy fraley

    Starting today I am 5ft 3 and weigh 140lbs
    My goal is to loose twenty lbs
    I will post any results I get oatmeal is very filling and I am determined
    Eat to live don’t live to eat

  • rhaz

    Hi! I have been trying almost all the ways how to lose weight through working out vigorously, to doing shortcuts by taking diet pills. but always, it backfires at me when I would stop exercising and/or my body became ‘immune’ to food suppressant pills. Reading this blog I realized that three years ago, I’d done this ‘oatmeal diet’ for three months, just plain oatmeal three times a day and no sodas, I lost more than 70 lbs, but since I only eat oatmeal, no veggies or protein at all, I ended up at the hospital because of malnutrition hehehe. So it freaked me out. Really to a point that I stopped eating oatmeal. But I have to say it worked, this diet helps you to feel satisfied and you feel energetic without having those hunger pangs. I’m actually doing this again (I gained weight because of my stressful work, I overeat when I’m stress) but not like before where I only eat oatmeal, I mixed oatmeal with salads or fruits. no bread or rice, a piece of chicken/beef/chicken meat per meal. Only during dinner I have plain oats. No sodas for now. I hope, I can lose 40 lbs in two months before my boyfriend arrives. lol good luck to us guys!

  • Ash

    Oatmeal diet and 1 hour cardio (walking uphill on treadmill) 6 days a week for 3 months had me shed 58 lbs! I did take on injury and put back all the weight over a 2 year period. I finally got fed up with taking back on a sedentary lifestyle and got my fat ass back in the gym and ate to fuel my workouts and not my taste buds. 3 months, 29 lbs down and putting on lean muscle =)

    Folks there’s no secret here! Burn more calories than what you put in and the weight will come off! Get off your ass and move!

    • Yvette

      When you started did you eat nothing but oatmeal for the first week? Basically did you strictly go by the diet?

    • China

      @Ash within those 6 days did u eat oatmeal only? Or did U have oatmeal for breakfast and lunch then eat salad for dinner? I’m beginning the oatmeal diet 6 days a week as well today.

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