Metabolism Booster Smoothie

This metabolism booster smoothie is like jet fuel for your metabolism.

Metabolism Booster Smoothie

I drink smoothies all the time, and am always looking for new combinations to dress up my favorite green smoothies. Grapefruit has become a favorite! I love grapefruit, but buy it… then let it sit in the bottom drawer of my fridge for ages because I never feel like taking the time to cut the sections. Now, I just cut them up, remove the peel and any excess pith, and freeze. By itself with spinach, it makes a very tart smoothie (I enjoy them though!). For this smoothie, I took advantage of some other fruits with great metabolism boosting effects to sweeten it up and make it even more delicious.


Studies have shown eating grapefruit or drinking grapefruit juice, without any other dietary changes, results in weight loss. However, people who eat fresh grapefruit lose more weight than juice drinkers. In this smoothie, the whole grapefruit is eaten, rather than just extracted juice.


Pineapple is high in vitamin C, a compound important for a healthy metabolism. Vitamin C deficiency lowers your body’s ability to oxidize fat. This leads to fatigue, and retention of body fat. One cup of pineapple has 131% of the RDA of vitamin C! This smoothie recipe has over 200%.

Green Bananas

I freeze bananas for smoothies and to add to my yogurt while they are still green (they are good– it just takes a bit getting used to since they are less sweet). The reason for this is green bananas are higher in resistant starch, and lower in simple sugars. Our bodies can’t break down resistant starches, but they help the body absorb vitamins and minerals (especially calcium, ladies!), and inhibit the growth of disease-causing bacteria. Those are great benefits alone, but the other great benefit is that your body can only extract half the amount of calories from resistant starch than from other types of starches (this doesn’t mean your green banana has half the calories of a ripe one- because the whole banana isn’t made entirely of resistant starch or sugar).

Whey Protein

Anyone who has drank a smoothie with a scoop of whey protein powder knows the belly-filling effect of protein. However, the benefits of protein to weight loss go beyond satiety. Our bodies have a more difficult time holding on to calories from protein, meaning we burn more calories digesting it than calories from carbohydrates or fats. One high protein smoothie isn’t going to have a huge effect on weight loss, but studies show that increasing protein intake over long periods of time has a significant impact on weight loss. Studies suggest that a protein shake with about 160 calories, and 25 grams of protein, can increase metabolism by 25%!


Spinach is actually more nutrient dense than kale. Calorie for calorie, spinach has 50% more protein, almost 350% more iron, and 30% more calcium (Kale does win the “nutrient battle” for Vitamin C!- so I wouldn’t say give up on kale just yet. It’s still super nutritious).

Spinach vs. Kale[Source- Google]

Green Tea

All the time, we hear that green tea is good for our metabolism, but why exactly? Caffeine does have a positive effect on our metabolisms, but the powerful component of green tea is a compound called ECGCs. ECGS have a thermogenic effect that increase fat burn in the liver, and also inhibit lipase, an enzyme that absorbs fat in the digestive tract. In addition to all of that, green tea has been proven to increase satiety, making you feel less hungry. If you’re looking for a great green tea, I love Organic Sencha.

Jet Fuel

If all that hasn’t convinced you to get in the kitchen and make this smoothie, let me just tell you IT’S DELICIOUS! And an eye opener. I’m struggling to get through the day because I just couldn’t sleep last night, and one sip of this smoothie has perked me up a lot.

Tips for Metabolism Booster Smoothie

  • I buy raw spinach frozen in ice-cube sized chunks. It’s super handy to have in the freezer for whenever I need a healthy smoothie. It also ensures my smoothies are extra cold and thick, just how I like them. If you don’t know where to buy them, make your own (it’s a great way to use up fresh spinach before it goes bad!). Just add to your blender with 1/2 or so of water, blend until the spinach is broken up, then drain the excess water, and spoon the spinach into an ice cube tray. After frozen, keep store in a sealed freezer bag.
  • I love Biochem Natural Whey Protein Powder. It’s grass-fed whey, and it’s unflavored, meaning to artificial flavors or sweeteners. Keeping chemicals out of your diet is as important to your metabolism as what you keep IN your diet!

Grapefruit Smoothie

4.0 from 6 reviews
Metabolism Booster Smoothie
Prep time
Total time
A smoothie specially formulated to rev your metabolism and help burn fat. A delicious and eye-opening way to start the day.
Serves: 2
  • ½ cup strong brewed green tea
  • ¼ cup coconut milk
  • 1 cup pineapple (frozen)
  • 1 unripe banana (frozen in quarters)
  • 1 large grapefruit (peeled, chopped, and frozen)
  • 70 g spinach, frozen (you can use fresh, but the smoothie won't be as thick)
  • 4-5 large ice cubes
  • 10 g plain whey protein (or favorite protein powder)
  1. Add the liquids first, then the rest of the ingredients to a blender. Blend well, until the greens are well blended into your smoothie.
  2. If you don't like your smoothies thick (I like mine super frozen and thick), add more liquid, or omit the ice.
  3. The spinach I use comes frozen in ice-cube sized pieces. I use 7 frozen cubes.
I've found that my blender is able to make a thicker smoothie if I make 2 smoothies at a time. If you don't have someone around to share with, freeze 1! I keep my plastic cups from Starbucks, fill them up, and freeze, and then the next day I just defrost for about an hour and it's still very thick and sipable once I've stirred it well.

Oranges also work well in place of the pineapple.

Metabolism Booster Smoothie / A powerful blend of metabolism boosting ingredients into one creamy, delicious and filling smoothie!


The Effects of Grapefruit on Weight and Insulin Response, US National Library of Medicine

Vegetables and Fruits, Harvard School of Public Health

Pineapple Nutrition Facts, Nutrition Data

All About Resistant Starch, Precision Nutrition

Ripe vs. Unripe Bananas, One Green Planet

How to Raise Metabolism, eMed Expert


  1. says

    Wow this smoothie is just looking great. The greenish color is just lovely :). Making a smoothie with green tea is truly a great idea.As it has plenty of benefits .This smoothie will not just gives the immunity but also gives the young looking skin too due to green tea :) :)
    Surya Tejaswini recently posted…13 Health Benefits of CucumbersMy Profile

      • says

        Any downsides to substituting soy protein? This looks right up my alley, but I’m lactose sensitive. Do you know if it’d turn out the same? I can make it with whey protein for my husband and son though, they will love this!

        • says

          I can’t see why substituting soy protein wouldn’t work well! I’m allergic to soy, so can’t say for sure. I’m also lactose intolerant, but whey isolate only has small traces of lactose, so I tolerate it well. Let me know if you try it with soy! Enjoy.
          Michelle recently posted…Hello, Sunshine! July 14thMy Profile

        • Tracy says

          Use Sun Warrior or Garden Of Life plant protein powder instead of whey protein powder if lactose intolerant.

          • says

            Yes, those would be good options– but unfortunately, I have a life threatening allergy to peanuts and the legumes in the peanut family– and most plant based proteins have green pea or soy or lentil protein, all of which are big no-nos for me! Whey isolate is over 99% lactose free, only traces, so I do fine with it.

  2. Sarah says

    I Gawk at food gawker copy the recipe, and never bother to comment. Until this ! the ingredients are so simple, they seem like a strange combo but are perfect together. Amazing !

  3. Tiffany says

    This sounds so yummy, ok so what kind of green tea would you recommend getting, also what is 10g in cups as far as the whey protein goes. Do you recommend a certain type of whey protein powder. I am just getting started on changing how I eat so I’m new at the protein powder.

    • says

      I buy sencha green tea, but any high quality green or white tea should work fine. A shortcut I sometimes use is to use water, and a 1/4-1/2 teaspoon matcha powdered green tea.

      I post whey protein in terms of grams because different brands of whey come with different sized scoops. The brand I buy in the States- ( BioChem Ultimate Natural Whey Protein — has a 20 g scoop, so half of the scoop. I think it’s about 1 1/2 tablespoons, but don’t stress too much about the perfect amount! You can buy Biochem Whey at Fred’s or Whole Foods, but it’s cheapest ordered off Amazon.

      Mostly, I suggest buying a Whey Protein Isolate, as opposed to a concentrate, because the Isolate is just the protein, and the concentrate is only about 80% protein, with milk sugars as well. And also to buy a natural, unflavored Whey, to avoid artificial sweeteners.


    • says

      I am so glad you enjoyed it! I have been hooked on them for several months now. I make two, freeze one, and then take one to work frozen the next day… only takes an hour or so to defrost so I can stir and drink– and its still thick!

  4. Veronica Pockrandt says

    Is there something I can use besides bananas? I actually am intolerant of bananas so I have to avoid them. I’m actually finding it hard to find healthy smoothies for weight loss that don’t involve bananas or some sort of yogurt.

    • says

      That’s because bananas make smoothies so delicious. Sorry to hear you can’t have them!

      Mango is a great substitute for bananas. It adds the same sweetness and creaminess. I actually use mango, grapefruit, and green tea in smoothies all the time– with a bit of protein powder.


  1. […] I’ve talked before about how much I love Good Earth tea, but I have to share an iced tea “recipe” with you, because I’ve been loving it so much lately. I’ve been taking 1 herbal Good Earth (original) tea bag, and 1 sencha green tea bag, and steeping them in 1 mug of hot water. I let it cool for 5-10 minutes, then pour it over a glass of ice with a slice of lemon or orange. It’s so refreshing, and sweet, without any sweetener or sugar of any kind. It’s calorie free, and — bonus — the green tea gives your metabolism a boost. […]

Leave a Reply

Your email address will not be published. Required fields are marked *

Rate this recipe:  

CommentLuv badge