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O4Nutrition M.D.

Dr. Ahmad Nooristani, with over 15 years of medical experience, leads O4Nutrition M.D., focusing on breakthrough research in alternative medicine and bioavailable nutrition.

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from 93 reviews
Delicious

I drink this at night a few hours before bed. The first week I didn’t notice much of a difference, but after week two I noticed how much deeper I’m sleeping! How much more relaxed I am at night. I will definitely be keeping this in my routine.

Tiffany
O4N Calming Formula
Delicious and clean

I’ve tried dozens of vitamin powders shakes and pills. O4 Nutrition is by far the best one I’ve ever had!

Tiffany
O4N Superfood Formula

I tried a few supplements since my surgery, and relax is by far the best. I feel healthier and my mood has improved. I will be sticking with this one

Margaret H*****
O4N Calming Formula

Finding the right supplement after bariatric surgery can be tough. This product has made a noticeable difference in my health. The taste is pretty good too.

Edward K.
O4N Calming Formula

My nutritionist recommended this one after my surgery. It's been a few weeks and I feel better. I have more energy and I'm sleeping better. I'm very satisfied with this product

William R.
O4N Calming Formula

I have noticed that my sleep is better and I feel more relaxed. The calcium and Vitamin D3 are a plus too.

Karen D.
O4N Calming Formula

My friend suggested this product after her surgery and I gave it a try after mine. I'm glad I did. My energy is up and I feel like my overall health has improved

Susan B.
O4N Calming Formula

After my surgery, I was overwhelmed with nutritional advice. Relax has made it easy. It's got everything I need and I can see the difference in my health. I will keep using this.

Charles P.
O4N Calming Formula

My doctor was really stressing on calcium and Vitamin D3 after my surgery. Relax Nutrition has been a game-changer. It's easy to use and I actually enjoy the taste.

Donna G.
O4N Calming Formula

Am a few months post-surgery and was looking for a supplement that fits my needs. It came recommended, and am glad I tried it. Energy level is up and I'm feeling pretty good

John C.
O4N Calming Formula

My digestion is better, and I have more energy

Nancy D.
O4N Superfood Formula

I started using it after my surgery and it's made a big difference. My energy is up and my digestion has improved. Great product!

HAROLD_RICHARDS
O4N Superfood Formula

This product is a lifesaver and has good price for everything that is included....

Mary E.
O4N Superfood Formula

After my surgery, I was so confused about what supplements to take. Xtreme Nutrition has made it so easy. It has everything I need, and I feel healthier overall

Richard K****
O4N Superfood Formula

This is a great product for someone like me who has undergone bariatric surgery and need to supplement good stuff

Josephine T.
O4N Superfood Formula

Fitness Nutrition Line

Designed by Dr. Nooristani, this range aims to offer the ultimate in workout supplementation, supercharged with the all-important element - Oxygen.

Recognized for its key role in body function, our bioavailable liquid Oxygen fuels your cells, supports enhanced energy and stamina, and promotes faster recovery.

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Find Your Ideal O4N Supplement!

Discover the supplements that suit your lifestyle and health goals best with our insightful quiz.

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How Does O4Nutrition Fitness Line Enhance Your Performance?

  • Powering Energy Generation

    or exceptional performance, your body relies on a process known as aerobic metabolism. This essential process utilizes a steady supply of oxygen to transform glucose into usable energy for your muscles.

  • Overcoming Oxygen Shortfalls

    During high-intensity exercise, your body might face an oxygen deficit, making it harder for your muscles to maintain optimal performance. This is where O4Nutrition steps in.

  • Boosting Performance with O4Nutrition

    Our unique formula elevates the oxygen levels in your blood, aiding in more efficient energy production. By extending the duration of the aerobic metabolism phase, O4Nutrition helps to reduce the build-up of lactic acid, often associated with muscle fatigue and discomfort. The result? Enhanced performance, greater stamina, and a faster recovery. Experience the O4Nutrition difference today!
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Bioavailable Oxygen in Our Fitness Line:

  • Key to Vitality

    Bioavailable Oxygen, a core ingredient in our supplements, plays a crucial role in various biological processes, including cellular energy production, which is key for function and recovery.

  • Energy Amplified

    Our oxygen-infused formulas assist in converting nutrients into usable energy, powering up your stamina and vitality.

  • Performance Optimized

    The oxygen in our supplements helps enhance muscle function and endurance, empowering you to extend and intensify your workout sessions.

  • Swift Recovery

    Leveraging oxygen's healing properties, our supplements facilitate tissue repair, promote faster healing, and help clear lactic acid to reduce muscle fatigue and soreness.

  • Boosted Immunity

    Our oxygen-enriched supplements support a robust immune function, fostering a more effective immune response.

  • Maximized Bioavailability

    The oxygen infusion in our supplements ensures increased bioavailability, promising maximum efficiency and benefits from each dose.
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Complete Nutrition Line

The Complete Nutrition Collection from O4Nutrition is a specially curated range of wellness supplements designed to optimize your health and vitality from the inside out.

Learn more about the Complete Nutrition Line:

O4Nutrition M.D. Quality

  • Developed Through Sound Science

  • Top Rated and Reviewed

  • We Test & Re-Test For Quality

  • FDA-Registered Facility

  • GMP Certified Manufacturing

  • Made in the USA

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The Complete Nutrition for Post-Bariatric

Experience the power of comprehensive nutritional support with O4Nutrition's Post Bariatric Line. With two uniquely formulated products - Superfood and Calming Formulas - we bring together all the necessary ingredients to promote faster recovery and sustainable health following bariatric surgery. Designed in line with ASMBS guidelines, our supplements are your ideal partners on your post-surgery wellness journey.

ASMBS standards, essential nutrients, post-bariatric.

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Bariatric Surgeries: A Nutritional Perspective

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  • Gastric Sleeve

    Also known as Vertical Sleeve Gastrectomy (VSG), this surgery reduces the stomach size, leading to potential deficiencies in protein, thiamin, cobalamin, folate, vitamin D, and zinc, often extending to calcium and iron post-surgery.

  • Gastric Bypass

    This surgery involves restructuring the stomach and small intestine, which could lead to nutrient deficiencies, including protein, thiamin, cobalamin, folate, vitamin D, zinc, and additional deficiencies such as calcium, vitamin A, pyridoxine, vitamin C, iron, and copper after surgery.

  • Gastric Band

    This procedure restricts the stomach's capacity, and can result in deficiencies in protein, vitamin A, thiamin, pyridoxine, cobalamin, folate, vitamin C, vitamin D, zinc, and selenium, often adding calcium and iron deficiencies post-surgery.

  • Duodenal Switch

    This surgery reduces stomach size and reroutes the intestines, leading to potential deficiencies in protein, vitamin A, thiamin, pyridoxine, cobalamin, folate, vitamin C, vitamin D, vitamin E, zinc, selenium, and additional deficiencies such as calcium, iron, vitamin K, magnesium, and potassium after surgery.

  • Gastric Balloon

    This procedure restricts the stomach's capacity, potentially causing deficiencies in protein, vitamin A, thiamin, pyridoxine, cobalamin, folate, vitamin C, vitamin D, zinc, selenium, and typically additional deficiencies in calcium and iron post-surgery.

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Learn more about the Bariatric Nutrition Line:

O4Nutrition Wellness Team

  • Hailey Esdaile

    Registered Dietitian

  • Cece Catena

    Registered Dietitian

  • Christopher Taglias

    MD, FACS, DABOM 

  • Dr. Ahmad Nooristani

    MD & Founder of O4Nutrition
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Join Our Wellness Ambassadors

Be part of our passionate advocates' community that trust O4Nutrition for their journey towards optimal health and fitness.

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O4Nutrition Apparel Collection

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Join the VIP Club and Reap the Benefits

Becoming a member of the VIP Club is absolutely free, and you'll start enjoying the rewards immediately upon signing up.

Create your account now and receive a 100-point signup bonus as a welcome gift!

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Shop By Your Goals

  • Fitness Nutrition

    Elevate your athletic performance with our specially-formulated sports nutrition supplements

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  • Complete Nutrition

    Meet the nutritional demands of your busy life with our comprehensive, bioavailable supplements.

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  • Bariatric Nutrition

    Support your bariatric journey with our tailored, easily absorbable, nutrient-rich supplements.

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