Weight loss pills: How do they work and are they effective?

Unless you've been living under a rock, you would have heard about weight loss drugs — from weight loss injections to weight loss pills.

You might even be curious about these weight loss medications and wondering if it's an option worth exploring, especially with so much information hitting the headlines and your social media feeds.

Weight loss medication is used to help people with obesity or those who are overweight with long-term weight management in combination with lifestyle changes like following a balanced diet and increasing how much exercise they fit into their week.

If you've been on a journey trying to lose weight and are considering all your options, we're diving deep into everything you need to know about weight loss drugs, how they work, how effective they are and what alternative prescription weight loss drugs are on the market.

What are weight loss pills?

Weight loss pills are a type of weight loss medication administered orally to treat obesity in combination with lifestyle changes like following a reduced-calorie diet and increasing physical activity.

Much like other weight loss treatments, weight loss pills are prescription drugs that need to be discussed with your healthcare provider to see if they're right for you.

If you decided to go down the path of oral prescription weight loss medications, you have a few options. Weight loss pills approved for use in Canada to help people with obesity or those with a high body mass index (BMI) lose weight include: orlistat (Xenical), phentermine-topiramate (Qsymia), naltrexone-bupropion (Contrave) and semaglutide (Rybelsus).

Orlistat (also known as Xenical and Alli) is a type of weight loss pill that is available as a prescription from your doctor or is available in a lower dose form from a pharmacy.

The 20mg version of Orlistat is only available with a prescription if you have a BMI of 28 or more and also have a weight-related health condition or a BMI of 30 or more. Without a prescription, you can get a low-dose version of Orlistat called Alli.

To purchase Alli, you must be over 18, express that you are willing to make lifestyle changes like following a calorie-reduced healthy diet and have a BMI of 28 or over.

Orlistat works by preventing roughly 1/3 of the fat from food intake from being absorbed. Instead, the undigested fat is passed out with your bowel movements instead of being absorbed by your body [1].

Lipase, an enzyme contained in the digestive tract, works to break down dietary fat into smaller parts that are used or stored for energy. Orlistat blocks the lipase so the fat isn't broken down and is moved through bowel movements [2].

Do oral weight loss medications work?

Like all weight loss solutions, weight loss medications are not a magic, quick-fix solution. It's important to remember that weight loss and weight management require lifestyle changes that you can keep up with over the long term.

But weight loss medication can be helpful for some people.

Research shows that those taking Orlistat who also reduced their calorie intake and increased physical activity lost weight by 10% more on average in one year than those who weren't taking Orlistat [3].

Other studies have shown that among people with obesity, those taking Orlistat saw a 5.63% weight reduction in comparison to 2.3% in the placebo group [4].

However, it is recommended that Orlistat, as a weight loss treatment, should only continue past 3 months if 5% of your body weight has been lost, as Orlistat can affect how you digest fat within 1-2 days.

After the 3-month mark, if you haven't seen weight loss improvements, the medication is likely to be ineffective for you [1].

What are the side effects of weight loss pills?

Weight loss medication can come with some side effects, so it's important to consider both the common side effects and severe side effects that are associated with these medicines.

The most common side effects of Orlistat happen as a result of the fat being passed out of your body with bowel movements.

This might result in fatty and smelly stools, an increased urge to go to the toilet and oily spotting on your underwear. These side effects can be curbed by following a low-fat diet and tend to go away over time [5].

In rare cases, there are more serious side effects, including [5]:

• Changes in hearing
• Diarrhea
• Dark, bloody, or cloudy urine
• Painful urination
• Fast heartbeat
• Ear aches

What are other types of weight loss medications available?

Aside from weight loss pills, there are other weight loss medications you can consider, including weight loss injections that are designed to help with weight loss and weight management.

In Canada, other prescription weight loss drugs that are approved include Ozempic and Wegovy (which contain the active ingredient semaglutide), and Mounjaro and Zepbound (which contain the active ingredient tirzepatide).

The main difference between these two groups of weight loss drugs is how they work in the body. Ozempic and Wegovy both use a substance called semaglutide, which helps control appetite and slow down how quickly food leaves the stomach. On the other hand, Mounjaro and Zepbound use a different ingredient called tirzepatide, which targets more than one hormone. This means Mounjaro and Zepbound could have different effects or side effects compared to Ozempic and Wegovy. So, while all four drugs help with weight loss, they do it in different ways.

All of these drugs can help people with obesity who have a body mass index (BMI) over 30 or those who are overweight with a BMI over 27 who also have at least one weight-related medical problem [7].

What weight loss medications actually help you lose weight?

Prescription weight loss drugs can be really effective and helpful in helping people reach a healthy weight. Let's take a closer look at these treatment options and how effective they are in aiding weight loss.

Orlistat

As we've already mentioned, research has shown that those using Orlistat as a treatment option who also followed a decreased calorie diet and increased their exercise lost weight on average by 10% more than those not taking weight loss medicine.

Ozempic

The most well-known amongst the weight loss medications. On average, people using Ozempic for weight management can expect to lose around 10-15% of their body weight over a year when combined with a reduced-calorie diet and increased physical activity.

Wegovy

Wegovy is a proven, effective weight loss medication and a smart alternative if you’re looking to reduce your treatment costs. It belongs to the same trusted class of GLP-1 medications as Mounjaro and delivers comparable results. In clinical trials, patients on the highest possible dose of Wegovy lost up to 20.7% of their body weight, showing that it can be highly effective when used consistently and with the right support [9].

Mounjaro

Mounjaro has shown significant effectiveness for weight loss in clinical trials. Participants receiving Mounjaro experienced notable reductions in body weight ranging from approximately 10% to 15% over a period of 16 to 72 weeks, depending on the dosage and study conditions. This weight loss is often attributed to its mechanism of action, which involves GLP-1 and GIP receptor agonism, leading to reduced appetite and increased satiety.

Zepbound

Zepbound (known generically as semaglutide) has shown promise in clinical trials specifically designed for weight management. For example, in clinical studies, participants using Zepbound experienced an average weight loss ranging from 15% to 20% of their body weight over 68 to 72 weeks, depending on dosage and adherence to a diet and exercise program.

Comparing the weight loss drugs

When comparing the weight loss drugs, Orlistat shows the weakest weight loss results, with only 10.2% of patients losing 10% of their body weight, while 66.1% of patients taking Wegovy lost 10% of their body weight [11][12].

A 2021 study about the effect of a comparable medication available at Juniper, at 68 weeks, 69.1% of participants had lost more than 10% of body weight, and 50.5% had lost more than 15%. The average weight loss after 68 weeks is 14.9%, and one in three participants lost at least 20% of body weight [14]. 

An holistic approach to weight loss

At Juniper, we combine weight loss medications with dietitian-led health coaching and tracking, so you can lose weight and reach your goals for good. 

Kickstart your weight loss journey with Mounjaro, Ozempic, Wegovy or Zepbound. These groundbreaking weight loss medications mimic the GLP-1 and GIP hormones, respectively, to help control cravings, delay stomach emptying, and keep you feeling fuller for longer. 

Plus, we have a team of expert dietitians and health coaches you can consult with to help you work through any challenges you're experiencing during your weight management journey. This approach sets you up for sustained weight loss, rather than a quick-fix solution.

This means you can continue to enjoy the things you love in moderation without ever feeling deprived.

Ready to see if Juniper is right for you? You can check your eligibility here.