What to Eat While Taking Phentermine

What to Eat While Taking Phentermine

At the start of your weight loss journey, it can be difficult to know exactly what to eat while taking phentermine.

There are so many diets and eating plans to choose from, and it’s no different when you’re taking phentermine.

Although you will experience a suppressed appetite, it is still very important that you eat well and make the right food choices.

Choose Your Eating Plan of Action

When there are so many contradicting views from one diet to another, it can be difficult to know which diets will work better for you, what to eat to lose weight, and which foods you should avoid.

For example, some diets will praise the benefits of complex carbohydrates, whereas others will tell you to avoid carbs altogether.

While it can be difficult to know who to believe, first, you need to think about what you feel able to do and whether it will work for you.

Some people find that they cannot seem to lose weight if they continue eating carbs, so if this is true of you, then limit your carbs and fill up on more fiber, protein, and vegetables instead.

If you’re not sure what works best for you, then switch from week to week and see when you make your biggest losses.

Whichever route you take, there are some universal dieting truths that will complement any sensible, healthy eating plan you wish to follow.

You Need to Eat to Lose Weight

You Need to Eat to Lose Weight

It is very important that you eat enough actually to be able to lose weight.

Not providing your body with enough food will cause your body to conserve any food you do provide as fat.

It is generally thought that the minimum amount of calories you should consume each day is 1200, but the exact amount you should eat depends on your sex, age, height, and starting weight.

Your phentermine doctor should be able to advise you on how many calories you need each day. You must also ensure you use your calories wisely and consume the right foods to maximize your weight-loss potential.

What To Eat On Phentermine

Water: The first rule of every diet is to drink lots of water.

When taking phentermine, you should be drinking at least 8 glasses of water per day to improve the functions of your body and assist in the release of water weight, as well as keeping you hydrated and less likely to misinterpret thirst for hunger.

Chilled water tastes better and is easier to absorb for the body, or if you want something warming, green tea is similarly hydrating and counts towards your daily quota.

Protein: When dieting, you must consume enough protein.

One reason for this is that high-protein foods take more work to digest, metabolize, and use, which means you burn more calories processing them.

They also take longer to leave your stomach, so you feel full sooner and for a longer amount of time. Protein is doubly important if you’re exercising as well as dieting to make sure you’re losing fat and not muscle.

Your body uses protein to build lean muscle, which not only makes you stronger and more toned but also burns calories even when you’re not active, unlike lazy fat, meaning your metabolism works at a higher speed.

Good protein sources are skinless chicken and turkey, tofu, fish, low-fat dairy, lean beef, eggs, and nuts.

Fiber: While fiber is not a magic weight-loss weapon, healthy high-fiber foods make you feel full, so you can resist eating more food than you need.

Although phentermine will help suppress your appetite, when you are hungry, opting for high-fiber food means that your appetite will be satisfied with fewer calories and fat.

Great sources of fiber are beans, whole grains, brown rice, nuts, baked potatoes (but you have to eat the skin), berries, bran cereal, and vegetables.

Fruits and Vegetables: The water and fiber in fruits and vegetables will add volume to your dishes, so you can eat the same amount of food with fewer calories.

Most fruits and vegetables are filling and naturally low in fat and calories.

Choose whole fruits over juices to maximize the fiber content, and always make sure your vegetables are cooked healthily and served with healthy dressings.

Alkalizing Foods: To maximize the effects of phentermine, it is necessary to have an alkaline urinary pH (7.5 to 8.0), as this means the phentermine will be excreted from your body at a slower rate.

Almost all fruits and vegetables are alkalizing, so they will help you maintain the alkaline levels in your body.

Therefore you will feel the effects of phentermine, such as higher energy levels and a suppressed appetite, for longer throughout the day.

Other alkalizing foods are almonds, chestnuts, tofu, stevia, cinnamon, curry, ginger, mustard, chili pepper, and all herbs.

What to Avoid

Simple Carbohydrates: Foods that contain simple carbohydrates include table sugar, products with white flour, candy, chocolate, cake, jam, cookies, soda, and packaged cereals.

They are digested quickly by your body, resulting in dramatic changes to your blood sugar levels, and they are not utilized by your body as fuel, often becoming stored as fat instead.

If you do include carbs in your diet, make them complex carbs; these take longer to digest and are packed with fiber, vitamins, and minerals.

Examples include vegetables, whole grain bread, oatmeal, legumes, brown rice, and whole wheat pasta.

Sugar: Added sugar supplies a large amount of fructose, which can only be processed by the liver. If the liver is already processing foods, the extra sugar gets stored as fat.

Sugar directly increases your chance of becoming obese due to elevated insulin resistance, as well as increasing cholesterol levels and your chances of getting diabetes.

Sugar can be found in many of the simple carbohydrates listed above and hidden in many processed foods, like frozen meals.

Dried fruit and store-bought fruit juices can also have high sugar levels, so fresh fruit and freshly squeezed juices are preferable.

Alcohol: Like increased sugar levels, alcohol can adversely affect your liver functions to the extent that your body’s fat-burning systems are inhibited for as long as several days; therefore, the liver has less chance to burn any fat.

Acidifying Foods: Besides being bad for weight gain and inhibiting fat burning, the foods above are also acidifying, meaning these foods are particularly important to avoid for those taking phentermine.

The reason for this is that acidifying foods increase the excretion of phentermine, meaning it will not last as long in your system as it should.

So, keep clear of soda, alcohol, coffee, sugar, butter, ice cream, and white flour products.

While taking phentermine, it is important to get into the habit of eating the right foods to re-educate your mind into providing your body with the best.

When you reach your goal weight, it is the changes you make on your weight loss journey that help you to maintain your new body.

All that said, the odd treat here and there will mean you don’t feel deprived and end up binging and undoing all your good work along the way.

If you’d like to share these tips or save them for later, check out this infographic!

Did you find this article useful? Or, do you know any other tips on what to eat while taking phentermine? We would love to hear from you! Comment below!

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  1. I started phentermine 10 days ago and have only lost 3 lbs. so far. I have been eating a low calorie, healthy diet with protein, vegetables, 1-2 servings of fruit, etc. and have not been seeing the results my doctor said I would. I know everyone loses weight differently, but what can I do to see the results I want? I also cannot exercise right now because I am recovering from ankle surgery.

    1. Hi Tracy,
      This article explains the most common reasons why people don’t lose as fast or as much weight as they had hoped to on phentermine: https://www.phentermine.com/blog/why-not-losing-weight-with-phentermine/. And, as we explain here: https://www.phentermine.com/phentermine-stopped-working/, you can do some exercise – just focus on your upper body. So, lift weights sitting down, do abdominal work and then start on low-impact exercise such as swimming when your ankle has healed.
      Sally, phentermine.com

  2. I just started phentermine today my worry is the side effects I’m on blood pressure medicine but with it my blood pressure is under control. How can phentermine effect your heart rate and blood pressure?

    1. Hi Tiffany,
      You can see more about how phentermine affects the heart here: https://www.phentermine.com/phentermine-side-effects/heart-problems/ If your doctor is happy to prescribe phentermine alongside your BP medication then he or she must consider it safe to do so, but just keep an eye out for side effects that cause concern and report them to your doctor as soon as possible.
      Sally, phentermine.com

    2. I was told by the Dr. that they monitor your BP while on Phentermine because it does raise the BP & your heart rate. You’re basically taking legal speed. Don’t plan on taking a drug test for work, etc while taking it because it will show up.

  3. Hello Sandy
    I been taking phentermine 37.5 for 6 days now, the 1st day I felt the dry mouth & super enegy in 2 days I lose 4 lbs none ever since. No side effect I feel as if its not even working. I start to feel hungry in the evening. How much calorie I should be consuming, I feel that’s got to be something wrong that I’m doing. now I went from start weight 203lbs in 2 days 199lbs and 199.8lbs. I am not happy.

    1. Hi Ivette,
      Your calorie limit depends on your height and activity level as well as your weight, but it should never be less than 1200 per day. It could be that you’re not eating enough, although phentermine isn’t meant to completely take away all hunger, as that would be counter-productive to your ability to keep the weight off. It’s meant to reduce your hunger to a manageable level so that you can learn how to eat better, so maybe rather than concentrating solely on calories you should ensure that you eat enough protein and fiber to keep you feeling full, as well as drinking lots of water. As far as the weight loss goes, 4lbs in six days is great, and shows why you shouldn’t weigh every day. Had you waited a week you would have been happy to lose 4lbs. Ensure that you’re getting plenty of sleep, that you’re taking care to manage stress and prioritize health as well as continuing to eat nutritious food and exercise daily and the weight will start to come off again, you just need to be a little more patient.
      Sally, phentermine.com

  4. Hi Sally,
    This is a very informative article. And all the comments are most helpful. Thankyou.
    I just started taking Phentermine again for the 3rd time. The 1st time I was 326 in September of 2014 and by December 2014 I had lost 48 pounds! I was so happy! Then in January of 2015 I found out I was pregnant. So I had to put my diet on hold for a while. I ended up gaining back 30 pounds. Very upsetting. When my baby turned a year old in October 2015 I went back on phenterine and lost about 10 pounds only to find out in December of 2015 I was pregnant yet again! Very frustrating I must say but I do love my babies. I just had my baby this year August 2016 and now I went back to the doctor to restart my phentermine. I’m not waiting a year again. Started on Friday October 7th at 309 and today is Tuesday October 12th and I’m already down to 300. I really love taking phentermine because I feel full all day, have the extra energy I need, and it works! The weight definitely comes off! Interesting story I know. Now my questions for you is, Is it ok or good to drink Arizona Green tea with Ginseng and Honey? Will grapefruit help or harm while taking phentermine? And is okay to use phentermine longer than 3 months? Thanks for your feedback.

    1. Hi Angela,
      We’re glad that you found the article helpful! Green tea is fine with phentermine, as is grapefruit. Green tea helps to boost metabolism and is hydrating too so it’s a great drink choice other than water, and grapefruit is an alkalizing food so it won’t cause phentermine to be expelled from your system quicker like acidic foods do. In reference to your last question, although phentermine is designed to be taken short-term, we talk about the 12 week period as this was the original length of time that phentermine was tested and approved for. Phentermine can be taken for longer but loses its efficacy after several months, and for some people this happens even sooner. For this reason many doctors advise customers to take it for 3 months and then have a break from it for a month, although some will prescribe it continuously for longer. So, while it can be taken for longer than 3 months, it is not intended as a long term solution and should only be used as a catalyst for a healthier lifestyle.
      Sally, phentermine.com

  5. I just starting taking phentamine 2 days ago, which I normally take at 5am. I was wondering if it’s safe to drink iaso tea or apple cider vinegar & water?

    1. Hi Vivienne,
      I’m not sure what iaso tea is but tea is fine with phentermine, and if you can stomach it, apple cider vinegar is said to have many health benefits, so it certainly won’t do you harm to drink it alongside phentermine.
      Sally, phentermine.com

  6. Sally,

    I read your detailed and supportive response and could not help but to say – thanks for your efforts.

    My situation is quite similar to Rofelina and I was wondering if cherries/mangoes are negative foods to intake on the Phentermine life change journey. I a fin·ick·y eater and very health conscious so I am doing my proteins, my fruits, 6 small meals (eggs fruits, nuts, grilled chicken salad, fruits, water, activa yoghurt, 2 sliced cheese – just a scenario). I drink lots of water but gained back some of the weight I losses.

    Could it be the grapes, banana, cherries, mangoes?
    Yoghurt since it has 18 grams of sugars?
    Coconut water is being substituted for water in some instance.

    Thanks a million!

    1. Hi Erin,
      Cherries and mangoes shouldn’t cause any problems losing weight with phentermine. Most fruit is alkalizing (except blueberries, plums, prunes and cranberries) so cherries and mangoes are fine in that regard. Bananas can be quite high in sugar so they are best consumed with something to neutralize the sugar, such as nut butter or cinnamon. Yogurt should always be sugar free – it’s more important to watch out for the sugar content than the fat content, although ideally low fat unsweetened yogurt is the best option for weight loss. What about vegetables? These are often a better option than fruit as they provide fiber, nutrients and no sugar.
      Sally, phentermine.com

  7. Hi i have been taking half of a 37.5 mg phentermine tablet since July 13th. My start weight was 220.8. Lost 7 pounds by July 27th. By July 29th I had gained 4.8 pounds. I have been doing 1 hour of boot camp 3X a week. Doing 1 hour brisk walk 5x a week. Just incorporated weight lifting last Thursday. I have been eating high protein low carbs plenty of water. Drinking a total soy protein for breakfast. Had changed the soy protein shakes for Whey protein (premier) last Monday. What could be causing the weight gain. I think it was the whey protein. Thank you in advance for your input.

    1. Hi Rofelina,
      Your weight can fluctuate depending on water intake, salt intake, monthly cycle etc, and gaining 4.8lbs in 2 days would suggest that this isn’t actually weight gain, but more like fluid retention or something similar, so we’re sure that your weight will drop again if you continue to make healthy choices. However, we don’t think that protein shakes are any substitute for real food, especially as you are working out so much. In addition, your body needs carbs to fuel these workouts so we think that it could be a good idea to eat more carbs, especially before a workout – without the proper fuel before exercise your body doesn’t end up burning as much fat and calories and often uses lean muscle for fuel instead.
      Sally, phentermine.com

  8. Hi I have been on phentermine now for 2 months and 11 days and I started at 398 lbs and am now at 342 lbs, so 56 lb weight loss and my doctor was pretty shocked with this. I can’t tell other than in certain pants I wear they are a little loser. I’m up at 5 am to go to work then take my pill at 7am and I drink a protein shake at 8am then by lunch at 11:30 am I’m not hungry so I force myself to eat lunch then I don’t eat again till 6pm at dinner. It seems to be working and I can definitely tell my stomach has shrunk because I don’t take the pills on the weekend and I still can’t eat very much. My question is does anybody know if it’s safe to lose that much weight in that amount of time?

    1. Hi Jessieca,
      You have lost a lot of weight very quickly but you started off at an extremely high weight, so percentage-wise, this is similar to someone who weighs 200lbs losing around 25lbs. Generally it is easier to lose weight quickly at first on phentermine because of the sudden change of lifestyle and eating habits, although your losses will probably slow down. If you’re not currently exercising we’d advise you to ask your doctor about starting as this will help to ensure that you’re losing fat and not muscle, which will help your metabolism and make it easier to keep the weight off for good.
      Sally, phentermine.com

      1. Ok thank you and when I first started for the first 3 weeks I was in the pool exercising 4 days a week for 2 hours a day but I had to stop due to personal stuff I had to deal with but fixing to start again. I started the pills to get my motivation up along with making myself eat less and eat better and so far it has worked I just need to make more time to work out.

          1. Hi Jessieca,
            That’s great – water helps a lot with weight loss, and swimming is an excellent exercise to work the whole body, but remember not to overdo the water or the exercise – as we explain here: https://www.phentermine.com/blog/going-extremes-phentermine/, too much of anything isn’t good for you, so remember not to drink more than around 2.5 liters of water a day and try to alternate swimming with other forms of exercise, as 2 hours per day is quite a lot.
            Sally, phentermine.com

  9. I have been on Phentermine for 2 weeks now and have lost 13 pounds (started at 175). I am keeping an Excel spreadsheet to track my progress. Weight, measurements, calories consumed, calories burned (which I get from FitBit since it incorporates your BMR with your activity…makes it easy) and calorie deficit (3,500 calories is 1 pound of fat. I am aiming for a 7,000 calorie deficit per week), fiber, fat, carbs, and protein, and water plus a small space to journal my food choices and anything else I feel is pertinent to my journey. I eat 1200 calories per day and keep my nutrient content amounts (fiber, protein, etc) in the range recommended for me. I make sure to drink at least 12 cups of water per day. I have found that adding a little grape steiva or orange stevia has been really helpful to get me to drink more. I realize that Phentermine is not for long term use so I am trying to make the most of my time on it to forge new habits that will allow me to continue making good choices after my prescription is done. Good luck all…

  10. I’ve been taking phentermine for 3 months. 18.75 mg per morning. 20 pounds down in three months — awesome.

  11. Hey my name is Rashad and I just started taking the pills today, but if I was to just drink a lot of water and not eat a lot but eat a little bit, will I lost weight? I currently weigh 184 I wanna be like 160 and I don’t really have time to exercise

    1. Hi Rashad,
      Eating well and drinking lots of water can both help you to lose weight, but exercise is often found to be the factor that helps people to lose weight and keep it off. What’s more, exercise helps to tone your body and burn fat, so that you’ll achieve both the weight and the body shape that you want. Exercise doesn’t have to take up a lot of time – it’s better to be consistent and do 10 minutes every day if that’s all the time you can spare, so whether it’s a brisk stroll at lunchtime or a few toning exercises at home, we would really recommend that you try to fit exercise into your day.
      Sally, phentermine.com

  12. The water of life. Drinking fresh/filter water is essential for good health. I read all your article and understood that how that 8 glass water is essential for everybody per day. I’m happy to read it. Now I bookmark your site and visit again for new article.

  13. I have been taking qsymia for 2 and a half weeks now prescribed by my doctor. I just started the 30 day supply last week. I lost 5 lbs the first week taking the medication. And then all of a sudden I gained it all back over night and have not lost a pound since the first week. I eat 3 meals a day. Fruits for breakfast salads for lunch and salads or various portioned meals for dinner all under 1200 calories daily. I drink only water green tea and pepper mint tea. I have had no pop since i started this diet and pill. It just taste horrible. I workout 3 to 4 times a week. I’m around 215. 5’7. Even my Dr is kind of stumped by why I have not lost any weight. I’m curious for other opinions.

  14. Hi, I have been taken phentermine for almost 2 months – I was 152 and I am down 142. I do notice I get a lot of headaches and everything bothers me and my heart feels like there is a lot of fat around it is that normal?

    1. Hi Yolanda,
      The headaches are, unfortunately, a common side effect of phentermine – here are some tips to combat these: Phentermine Side Effects. The feeling you describe as being bothered by everything is quite common too – this article offers some tips on how to overcome this: Phentermine: Losing weight and not feeling great. I’m not sure what you mean about your heart feeling that there is a lot of fat around it. If you’re experiencing any pain then you should speak to your doctor immediately. Hope that helps!
      Sally, phentermine.com

  15. I just started phentermine 37.5 on 01/29/2016 the doctor also prescribed a water pill and topiramate 25mg and a water pill. My biggest concern is she told me do not exercise which I am not really sure about. Also I’m not sure why I’m on a water pill. Has anybody had the same advice or what do you suggest.

    1. Hi Felicia,
      It’s strange that your doctor has advised you against exercising – did she say why? In my experience, patients are only told not to exercise if they are at risk of heart issues when exercising or injury due to extreme obesity. Water pills are usually prescribed to expel excess water in your system, but they do mean that you need to be drinking even more water than usually advised. It could be a good idea to check with your doctor to see why she’s prescribed you them and what you need to do to make sure they work for you as she intended. Hope that helps!
      Sally, phentermine.com

  16. Hi , my name is sid. My auntie took phentermine and lost weight, but she only took it for a month – I just wanted to ask if we can drink milk, tea (which is water, milk and a lipton tea bag). In vegetables and fruits, which can we not eat like apples, oranges, bananas, watermelons, strawberries , (if in fresh orange or apple juice) in vegs like carrot , green peas. Also, what about plain unsalted peanuts, almonds, cashews, walnuts, dried fruit – which can we eat? So no bread, not even brown bread, and what about rice? Appreciate it, thank you.

    1. Hi Sid,
      The article is quite general so we weren’t able to write too specifically about all foods. However, I think you’ve misunderstood about the bread etc – we personally believe that you should be consuming all foods in moderation, but we also have to recognize that some people limit their carbs as a method to lose weight. We do say in the section on fiber that you should consume healthy sources such as brown rice and whole grain bread, as well as legumes, cereals, fruit and veg. We mention in the section on protein that nuts are a good source, and all the nuts you have listed are great, but you should always eat nuts in moderation as they are high in calories, so be sure to portion them out and not just eat them mindlessly. With respect to the fruit and vegetables you’ve mentioned, all fruit is fine and is a great source of fiber and nutrients. We would advise against fruit juice however as this is the fruit minus the fiber, which is mainly sugar. So, stick to eating whole fruits and vegetables. Milk is a great source of protein and calcium, and tea is also a good alternative to water, any type of tea is fine but green tea (if you like it) has more weight-loss-boosting properties. Let me know if you have any other questions, or if anything isn’t clear for you.
      Sally, phentermine.com

  17. Hi Sally
    I have been on Phen for about two months now and it doesn’t seem to be helping.
    I started taking it because I had hit a plateau that didn’t budge for about 4 months. I literally retrained myself to eat better and exercising. My weight at the beginning was 60 kg and is only at 58 currently.
    I gym for 45 minutes – an hour about 4 times a week, I take the pill (30mg) as soon as I wake up at 5:30 yet I am sleepy by lunch and funny enough I struggle to sleep at night. I am eating complex carbs and increased my protein intake because carbs kill me efforts.
    There are no huge side effects, but the energy and the appetite suppression is not that much.
    I’m now getting frustrated indeed. What could be the problem.

    1. Hi Anna,
      If you weigh 58kg, which is around 128lbs, you’re probably already at a healthy weight unless you’re under 5 feet (150cm) tall, so that is most likely why you can’t lose any more weight. I’m surprised a doctor prescribed it to you since it’s meant to be for obese patients who are unable to lose weight on their own. It sounds like you have a healthy lifestyle and as you’re at a healthy weight, I would just suggest you continue to exercise and eat well to maintain your healthy weight, and to help you tone up (if necessary), but it doesn’t sound like weight loss is something you need to strive for.
      Sally, phentermine.com

      1. Thank you Sally, yes I’m quite short, 143 cm and my BMI is a little over. My journey started last year at 68kg and it was hectic for me to even get to the 60 kg in April. I do have trouble sleeping though, work a 8h00-16h00 day and I study afterwards so it’s hectic for me to get even 7 hours of sleep at night. I think that maybe the problem too.

  18. I am currently on the Phentermine 30mg and haven’t lost weight. My only concern is I have PCOS and I have had PCOS since I was little. This has caused me to struggle with not just weight but with a number of issues. I can’t seem to loose any weight. I have been going to the gym Three to four times a week, taking walks, cutting soda out of my life and increasing water. At this point i am concerned. I also have started making very low carb meals seeing as how one of my family members is Diabetic. Is there a reason as to why nothing is coming off? Or could it be the PCOS?

    1. Hey Regan,
      It could be the PCOS, this certainly makes weight loss difficult. You may find this article and the comments helpful: https://www.phentermine.com/blog/phentermine-can-help-pcos/. We also just published an article covering the most common reasons why people find that they aren’t losing weight with phentermine, so maybe that could offer you some ideas: https://www.phentermine.com/blog/why-not-losing-weight-with-phentermine/
      Good luck!
      Sally, phentermine.com

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