In the world of weight loss diets, there are two contenders that people mention over and over again for their effectiveness: the ketogenic diet and WW (formerly known as Weight Watchers).

While the two approaches couldn’t be more different, both have amassed followings because of their results. Many people have reported weight loss success on both the points-based WW program and the low carb, high fat ketogenic, or keto, diet.

This article reviews how each program works, the benefits and downsides of both, and which is better for weight loss.

WWKeto
Dietary approachmoderation, points systemlow carb, high fat
Costapproximately $12–$34 per month, plus cost of groceriescost of groceries
Supportall paid levels of the program offer some degree of support
Sustainabilityallows all foods; subscription cost may affect long-term sustainabilitystrictly limits sugar and other carbs, including many everyday foods considered healthy, thus may be difficult to adhere to over the long term; no subscription cost
Weight losssome studies have found WW programs led to weight loss, but WW funded some of this researchsome studies have found keto diets led to more weight loss than low calorie diets

It is important to note that the grocery budget for each diet can vary based on the individual and their food preferences.

WW is a popular commercial diet program that has been around for decades. It’s built around the concept of moderation and portion size, and it allows followers to include any type of food they want in their diet.

WW assigns you a daily SmartPoints allotment and places you in one of three color-coded programs based on your weight loss needs. Here’s a brief overview of the colors:

  • Green: more SmartPoints allowed per day, with 100+ ZeroPoint foods, mostly fruits and vegetables
  • Blue: moderate number of SmartPoints allowed per day, with 200+ ZeroPoint foods, including fruits, vegetables, and lean proteins
  • Purple: fewer SmartPoints allowed per day, with 300+ ZeroPoint foods, including fruits, vegetables, lean proteins, and whole grains

Typically, the foods that are lower in SmartPoints tend to be lower in calories, fat, and sugar and higher in fiber and protein. High-point foods are typically high in calories, fat, or sugar — like french fries, ice cream, or fatty meats.

So, while you can include high-point foods, they’ll quickly use up your daily SmartPoints allotment.

WW is also a paid program. There are different tiers based on the level of support they provide. With purchase, you gain access to the WW tracking app and all of its included tools.

This table summarizes three WW plans:

Digital OnlyWorkshops + DigitalCoaching + Digital
Price$2.87 per week$5.88 per week$7.79 per week
What it includesfull access to myWW+ app and toolsweekly virtual or in-person workshops and Digital Only benefitsunlimited access to a personal WW coach and Digital Only benefits

Does it work for weight loss?

Yes, WW does appear to be effective for weight loss.

Several studies have found that WW helps people lose weight. However, it’s important to note that WW funded many of these studies directly or indirectly, which may have influenced results (1).

In one WW-funded study of 279 people, researchers found that those using the WW program lost more than double the weight of a control group in 3 months. The WW participants were also more likely to have maintained their weight loss 1 year later (2).

Another large WW-funded study including over 29,000 people found that, on average, participants lost about 6 pounds (3 kg) in 12 weeks. Approximately two-thirds of participants were able to lose at least 5% of their body weight (3).

Summary

WW is a paid diet program based on the principles of moderation and portion control. It uses a points-based system to encourage healthier diet choices. It appears to be effective for weight loss, though WW funded many of the studies.

The keto diet is a low carb, high fat, moderate protein diet that people originally used to help manage epilepsy. People now use it for a variety of other purposes, including weight loss and blood sugar management.

Unlike WW, it is not a commercial diet program and is instead an eating pattern. On keto, your body enters a state called ketosis — in which you burn fat, rather than carbs, as your primary source of fuel.

This offers a number of potential metabolic advantages for people who are trying to lose weight (4):

  • better blood sugar control and lower insulin levels
  • decreased appetite
  • maintenance of metabolic rate (calories burned at rest)
  • easier to burn stored body fat

The keto diet is low in carbs and sugars, so when you’re on it you need to avoid foods like:

  • bread
  • pasta
  • rice
  • potatoes
  • sweets and desserts
  • sugary sodas
  • even most fruits

On the other hand, you can safely include:

  • most meats
  • nonstarchy vegetables
  • nuts and seeds
  • full fat dairy products
  • low sugar fruits, like berries

Does it work for weight loss?

Yes, like WW, keto does appear to be effective for short-term weight loss.

Several studies have investigated the success of a keto diet for weight management.

A study including 89 people with type 2 diabetes and obesity found that participants following a keto diet lost significantly more weight and had higher reductions in their waist circumference after 4 months than people following a standard low calorie diet (5).

In fact, over 90% of the participants in the keto group lost at least 5% of their body weight during the study, and over 80% lost at least 10% (5).

Another review of studies including around 1,500 people that compared a keto diet with a low fat diet found that the weight losses of those in the keto group were significantly greater than those of the low fat group, at least until a 2-year follow-up (6).

Summary

Keto is a low carb, high fat diet that makes it easier for you to burn your own stored body fat for fuel. It may result in significantly more weight loss compared with a standard low calorie diet.

WW and keto each boast benefits beyond weight loss.

WW

WW has been around for a long time and has a proven track record of success.

One of the benefits of the WW program is that it provides a method of practicing moderation and portion control that’s simpler than calorie counting. It may also help you learn to make better food choices over time.

Even if you choose to stop the program, you can still use the principles you learn from WW to make better food choices.

WW also provides a built-in support network, even with its least expensive Digital Only plan.

This plan provides access to a members-only virtual community. Meanwhile, higher-priced plans offer even more accountability and support options, including online or in-person meetings and unlimited one-on-one coaching.

Keto

Likewise, the keto diet has numerous benefits.

One of the key benefits that many keto dieters report is how fast they’re able to lose weight on the diet. This may be due to several factors (4).

Being in ketosis seems to have an appetite-suppressing effect, making it easier for a person to eat fewer calories (4).

Additionally, the keto diet may reduce your insulin levels. Insulin is the hormone that signals your body to store excess blood sugar as fat. So, when insulin levels are lower, it may be easier for your body to burn its own stored fat (4).

It also regulates your blood sugar levels, which may help rein in hunger and food cravings.

There are also some case reports of people with type 2 diabetes drastically increasing their blood sugar control and reducing their need for insulin and diabetes medications after starting a keto diet (4, 7, 8).

Summary

WW provides interpersonal support to its participants and encourages moderation and portion control. Keto may help improve blood sugar levels and reduce your appetite, making it easier to lose weight.

Both diets have their downsides as well.

WW

One of the major downsides of WW is the price. Although it’s relatively inexpensive if you break it down per week, the costs can add up — especially if you’re on one of the more expensive plans and you want to stay on the program for a longer period of time.

Additionally, the SmartPoints system may inadvertently discourage you from consuming foods that are otherwise healthy, simply because they’re high in calories or fat.

These foods may include:

  • full fat dairy
  • avocado
  • natural fats and oils, such as olive oil

Keto

The keto diet has a few drawbacks. It’s a major shift from the typical diet most people eat, and for that reason it can be difficult to sustain long term. It may be particularly challenging to maintain during holidays or while vacationing.

The keto diet also excludes many otherwise healthy foods, like:

  • most fruits
  • beans and legumes
  • oats
  • sweet potatoes

Finally, there are some long-term safety concerns with the keto diet that scientists haven’t fully studied yet. These include its potential to increase your cholesterol levels, which may increase your risk of heart disease (9).

Summary

WW is a paid program, so the costs can add up if you’re on it long term. On the other hand, keto may be difficult to maintain because it’s restrictive, and there are some potential long-term health concerns that scientists haven’t fully investigated yet.

Both WW and keto diets may help you achieve short-term weight loss. Which diet is better for you depends on your individual needs.

WW may be a better option if you:

  • value the flexibility of eating any food you want
  • find the built-in structure and support of the WW program necessary to keep you motivated
  • are fine with the cost of subscription

On the other hand, keto may be a better option if you:

  • have type 2 diabetes or other blood sugar management concerns
  • find it easier to make healthier decisions when your food options are limited
  • are OK dieting independently or building your own support network
Summary

WW and keto each have their pros and cons. WW may be a better fit for some people, while keto will be a better fit for others. It depends on your personal needs and preferences.

WW and keto are two very different diets. WW is a structured, paid diet program based on moderation, portion control, and the WW SmartPoints system. It offers built-in social support at all paid levels of the program.

Keto, on the other hand, is a low carb, high fat diet that aims to get you into ketosis, thereby making it easier for you to burn your own stored body fat as energy.

Both diets are effective for weight loss, but for many reasons one may be a better fit for you than the other.