Flat Tummy Shakes Review

Do Flat Tummy Shakes Really Work? a Dietitian Review

Flat Tummy Shakes by Flat Tummy Co are a popular weight loss meal replacement shake that promises to help you lose weight quickly.

Many consumers wonder about their health claims and ingredients, as well as how effective they may be at helping them lose their stubborn weight.

This review is not a sponsored or affiliate post, but rather, an honest look at this product and its claims, from a registered dietitian.

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What Are Flat Tummy Shakes?

Flat Tummy Shakes are a meal replacement shake that serves as the cornerstone of their Flat Tummy Shake it Baby Program.

They are aimed at helping consumers lose weight and ultimately get a flat tummy.

It is a diet product marketed toward women, often calling their customers “babe,” and using light pink packaging.

It claims to help customers “move lbs,” or lose pounds.

These shake mixes feature protein, fiber, vitamins, minerals, probiotics, and digestive enzymes, plus an extract from Garcinia Cambogia.

It’s meant to be used as meal replacements, replacing two meals a day during their 2 to 4-week program.

The company Flat Tummy Co. has garnered attention with its pink and pastel Instagram posts, as well as receiving endorsements from several celebrities and social media influencers, such as Kim Kardashian.

They are also famous for their diet tea, Flat Tummy Tea, which was one of their first products before their Shake It Baby meal replacement program.

Flat Tummy Shakes Nutrition

Flat Tummy Shakes are a meal replacement shake that comes with 50 fruits and vegetables and an array of vitamins and minerals.

It’s vegan, keto, gluten-free, and dairy-free.

In a nutshell, here is what’s in Flat Tummy Co. Shake It Baby shake powder:

  • 22 g of vitamins and minerals
  • 20g plant-based protein 
  • Digestive enzymes
  • Super Citrimax 
  • Probiotics
  • 50 fruits and veggies including Brussel sprouts, bell pepper, sweet potato, sweet cherry, green bean, red pepper, black currant, broccoli, kale, flaxseed, eggplant, and pomegranate. 
  • Natural sweeteners like luo han guo (monk fruit)

It features a variety of vitamins and minerals including protein, dietary fiber, vitamins, minerals, as well as active ingredients from garcinia Cambogia, digestive enzymes, and probiotics.

The shake powder gets protein from plant-based protein sources, like peas and brown rice.

Flax and chia seeds are also included in this shake. It uses natural low-calorie sweeteners like monk fruit and stevia.

Two scoops of the powder contain 130 calories.

It also contains 20 grams of protein, 12 grams of carbohydrate, and 6 grams of fiber.

It is low in fat, with only 0.5 grams per serving.

It also contains vitamins A, C, D, E, and B vitamins, as well as minerals like iron, calcium, and zinc.

Nutrition Facts

Here are the nutrition facts of their chocolate flavor:

Serving size: 2 scoops (41g)

  • Calories: 130
  • Total Fat: 0.5g (1% Daily Value)
  • Potassium: 330 mg (9% DV)
  • Total Carbohydrates: 12 g (4% DV)
  • Dietary Fiber: 6 g (24% DV)
  • Sugar: <1 g
  • Protein: 20 g (40% DV)
  • Vitamin B12: 8335% DV
  • Vitamin B6: 100% DV
  • Vitamin D: 50% DV
  • Vitamin C: 40% DV
  • Vitamin E: 35% DV
  • Riboflavin: 35% DV
  • Pantothenic Acid: 35% DV
  • Folic Acid: 35% DV

Flat Tummy Shakes also contain magnesium oxide as a mineral source.

This form of magnesium is sometimes used to treat heartburn but also works as a laxative.

Continual use of magnesium oxide can interfere with the absorption of other nutrients. (1)

These shakes also use inulin, a type of fiber derived from plants like chicory root.

Food manufacturers often add this ingredient as a way of increasing the overall fiber content of their products.

Inulin is a fructan, a short-chain fructose molecule.

These fructans are a type of oligosaccharides or chains of sugars.

Fructans and oligosaccharides have been known to cause gastrointestinal discomforts, such as gas or bloating, especially in people with IBS, or Inflammatory Bowel Syndrome. (2)

Weight-Loss Driven Ingredients

Flat Tummy Co. promises their Shake it Baby mixes help ‘babes’ curve cravings, move the stubborn pounds, and cut calories.

Per their site, one ingredient behind the drive is Super Citrimax, which they clinically tested to be 3 times more effective than diet and exercise alone.

To get to the bottom of it, I dove into three of their main weight-loss ingredients and their latest scientific findings.

Digestive Enzymes

Digestive enzymes are supplements that can be used to help the body digest and process proteins, fats, and carbohydrates. (3)

Typically, the human body produces sufficient digestive enzymes to digest the food you consume.

Many people do not need digestive enzymes to help them digest and process proteins, fats, and carbohydrates.

Digestive enzymes have been shown to improve conditions like IBS, celiac disease, or lactose intolerance.

In particular, pancreatic lipase enzymes have shown some promise in this area. (3,4)

Additionally, there is some research that suggests that digestive enzymes may help the beneficial bacteria in your gut, but these are enzymes that target fiber. (5)

In regards to weight loss, the effect of digestive enzymes has had mixed results.

A recent study found that participants that took a fat enzyme before eating a high-fat meal experienced less fullness and satiety, which may derail weight loss efforts. (6)

More research has been done on weight loss and enzyme inhibitors, which would block the absorption of nutrients.

Particularly, lipase inhibitors, that block the absorption of fat, have been shown to help with weight loss. (7).

That said, Flat Tummy Shakes contain a digestive enzyme blend, Pepzyme AG. This contains proteases, meant to help digest proteins.

There is little research on protein enzymes aiding with weight management, so it’s unclear if the enzymes found in Flat Tummy Shakes are that effective or even necessary.

Super CitriMax

Flat Tummy Shakes contain Super CitriMax, or Hydroxycitric acid, an extract from Garcinia Cambogia. Super CitriMax is a supplement containing 60% Hydroxycitric acid.

The Flat Tummy Co. website claims that Super CitriMax is three times more effective than diet and exercise alone.

Hydroxycitric acid is derived from the peel of the Garcinia Cambogia fruit.

This extract is often touted to have weight loss benefits, but the research is mixed.

While there have been studies that have found success with Hydroxycitric acid and weight loss, there have also been others that have found no difference in weight when taking it (8).

In a review of twelve separate studies, participants that took the supplement lost a total of 2 pounds more than those who did not, over the course of 8-12 weeks.

Adverse gastrointestinal events were twice as likely in the groups that took Hydroxycitric acid. (9)

Other studies have found similar results with weight loss, appetite control, and loss of body fat loss, coupled with a heightened risk of gastrointestinal distress. (10, 11, 12)

However, other studies have found no difference between groups that took the extract and those that did not. There was no change in their weight, satiety, calorie intake, (13, 14, 15).

Currently, there is not enough evidence to support that Garcinia Cambogia or Hydroxycitric acid supplementation results in weight loss. More research is needed.


Probiotics are often referred to as “good bacteria” that live in the gut.

They are found naturally in fermented foods like yogurt, sauerkraut, kimchi, miso, and kefir.

There is evidence that probiotics carry several beneficial health effects. However, it is unclear if they make any difference in weight loss (16, 17).

Additionally, it has been shown that diets low in fiber will reduce the number of good bacteria in the gut, and can increase the amount of bad bacteria, which have been linked to higher rates of certain cancers (18).

The generally recommended amount of fiber is 25 g daily for women and 38 g per day for men.

Flat Tummy Shakes provide 6 grams per serving, which even if you drink two per day, is only half the recommended amount of fiber for women.

So it is important for consumers to eat plenty of fruits and vegetables while taking probiotics or drinking Flat Tummy meal replacement shakes.

What do Flat Tummy Shakes do? 

Flat Tummy Shakes are marketed as a meal replacement shake.

The Flat Tummy Co. website suggests replacing 2 meals with shakes daily under their shake program.

Each shake contains 130 calories. A typical meal can range from 400—700 calories or more. (frogbones)

By replacing a meal with a 130 shake, this drastic calorie reduction can result in weight loss and a huge calorie deficit.

Due to their high protein and fiber content, these shakes make leave consumers feeling full and satisfied for a few hours.

Do Flat Tummy Shakes Help You Lose Weight?

Owing to their low-calorie content, consumers may find these shakes help them lose weight by replacing two meals with two 130 calorie-containing shakes.

However, there are several shakes available on the market that may also offer similar calories.

Additionally, if consumers turn to high-calorie snacks or meals after consuming the shakes, this will derail their weight loss efforts.

Frankly, for most adults, 130 calories is a more appropriate caloric amount for a snack, not a meal.

Our bodies need sufficient fuel to carry out vital daily functions, and regular meals and snacks provide this.

Women should be eating at least 350 calories at meals, if not a bit more, and in addition to 2-3 snacks per day.

One common complaint noted in online reviews is that the shakes are expensive, and so consumers may not be able to afford to purchase this product to replace two meals daily for long periods of time.

When regular meals and eating habits are resumed, consumers are likely to regain any weight they may have lost.

Potential Side Effects 

While the official website does not disclose any side effects from this product, reviews posted on other retail sites do mention consumers experiencing a variety of side effects.

Common side effects from other meal replacement and protein shakes are bloating, gas, changes in bowel habits, gastrointestinal discomfort, upset stomach, and feeling hungry. 

These are likely due to inulin, the type of fiber used, the fiber content, the digestive enzymes, a response to the probiotic blend, or a reaction to certain ingredients.


Do Flat Tummy Shakes Work?

There are mixed reviews on Flat Tummy Shakes and their effectiveness.

By cutting two meals per day down to 130 calorie shakes, consumers may lose weight in the short-term, but will likely regain it when resuming regular meals without a healthy diet and exercise. 

Are Flat Tummy Shakes Vegan?

Yes, they are vegan. They contain no animal by-products. 

Are Flat Tummy Shakes Keto-Friendly?

Each serving contains 12 g of carbohydrates and 6 g of fiber, leaving 6 g of net carbohydrates.

Depending on your daily net carb goal, these shakes may fit into a keto diet pattern.

Do Flat Tummy Shakes Taste Good?

In general, this answer is very subjective and will vary from person to person.

There are mixed reviews on the taste. Some consumers write that these shakes taste great, while others state that they taste like vitamins or taste chalky.

As of now, their shake comes in three flavors, vanilla, chocolate, and strawberry. 

What Can I Drink to Have a Flat Tummy?

The old adage says, “The best diet is the one that you can stay on.”

This means finding a healthy eating pattern that works best for you and is sustainable. 

Diets rich in fruits and vegetables, whole grains, proteins, and healthy fats have been tied to many health benefits and can help maintain a healthy weight. 

Additionally, regular physical activity has been shown to improve your heart, respiratory, and mental health, help with good quality sleep, as well as lose weight, and maintain a healthy weight.

Find an exercise that you enjoy, whether it be dancing, lifting weights, practicing a sport, or going for a walk.

For a long-lasting and sustainable change in your weight and overall health, it is often best to find a healthy eating pattern and exercise routine that fits into your existing lifestyle.

The Bottom Line 

Flat Tummy Shakes claim to help consumers lose weight. They are marketed as meal replacement shakes.

Consumers are to drink a shake in place of two meals daily.

While these shakes may help you lose some weight due to their low-calorie content, they do contain ingredients that may cause unpleasant side effects for some.

Many participants using meal replacement shakes in general find that once they stop drinking the shakes and resume eating regular meals, they gain the weight back.


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