Keto vs. Low Fat

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Written by Rahul Malpe, Certified Nutritionist and medically reviewed by Abby Courtenay

Imge of Keto vs. Low Fat



Some people believe that a keto diet is the best way to shed pounds, while others say low-fat plans work just as well. To see why these two diets are so popular, we will compare them side by side, discuss their pros and cons, and finally determine which is healthier and more affordable.

What is a low-fat diet?

It is a way of eating that restricts fat and emphasizes foods high in carbs and protein. Foods high in fat are limited and replaced with foods such as lean meats, fruits, vegetables, and whole grains. 

This type of eating is often recommended for people who are trying to lose weight or lower their cholesterol.

Many of the foods included in the diet don’t have much fat naturally or are fat-free, such as fruits and vegetables. Processed foods may also be included in the diet, such as low-fat cookies and ice cream, which contain less fat than their traditional counterparts.

Similarities between a low-fat diet and keto 

You could say that these two approaches are somewhat opposite (fat intake is high for one and low for the other), so they share very few similarities. 

However, both emphasize eating whole, unprocessed foods and limiting the intake of refined carbs and added sugars. They also encourage choosing healthy fats, such as olive oil, avocado, and nuts.

Also, both these plans can be effective for weight loss.


Differences between low-fat diet vs keto

One of the main differences between these two is the macronutrient composition. A low-fat (LF) approach typically consists of 50-55% carbohydrates, 30% fat, and 15% protein, whereas keto consists of 5-10% carbohydrates, 20-25% protein, and 70-80% fat. 

This difference in macronutrient composition has different effects on the body. When carbohydrate intake is restricted, as it is in a ketogenic diet, the body enters a state of ketosis. This means that the body begins to burn fat for energy instead of carbs. 

Some people may experience negative effects such as headaches, fatigue, and nausea when first starting on keto due to the drastic change in their eating habits. However, these side effects typically subside after a few days or weeks. 

In contrast, a dietary plan that is low in fat does not typically lead to negative effects because it doesn’t cause you to go into ketosis.

Benefits of a low-fat diet vs keto

By following either of these two eating regimes, an individual may experience the following benefits.


Benefits of LF

Heart health benefits

Diet plays an important role in determining your risk of developing heart disease. 

There is an increased risk of heart disease associated with eating saturated and trans fats. Arteries can become clogged with fatty deposits, affecting the heart and blood vessels. The result is that the blood vessels become less elastic and are unable to flow freely. Heart attacks can result from these deposits breaking off and causing a blockage.

It has been shown that people whose diets are low in saturated fat see significant reductions in their total and LDL cholesterol. Studies have also found a reduction in heart disease risk with reductions in saturated fat intake.

However, it’s important to be aware that when you decrease your fats, you may be increasing your sugar. This is because many low-fat products may contain more sugar. 

Like saturated fat, added sugar is bad for your heart. So, to reap benefits for heart health on this plan, you should be eating foods that are naturally low in fat (fruits, veggies) rather than processed foods.
There are no forbidden foods

In comparison to keto, on a LF plan there are no foods that are specifically forbidden on this eating plan, as it is not a limiting one. As long as your total daily fat intake remains within your daily limit, even foods that are high in fat can be consumed in limited amounts.

Low-fat menu options are widely available without the need to purchase special meals. There are a wide variety of low-fat foods available in almost every grocery store, whether they are naturally low in fat or manufactured to be fat-free, you are sure to find many options that fit your budget.


Benefits of keto

Beneficial for type 2 diabetics

When you are eating carb-rich meals throughout the day, your primary source of fuel is glucose. They are quickly absorbed from the bloodstream which spikes the blood sugar. However since on keto, you have to restrict the number of carbs you consume your blood sugar and insulin levels stay stable. This may be beneficial for type 2 diabetics who suffer from insulin resistance and subsequent high blood sugar.

Aids weight loss

When you follow keto, your body enters a state of ketosis, in which it burns fat for energy instead of carbohydrates. This shift in metabolism leads to a reduction in craving for carb-heavy foods and an increase in fat burning, both of which can help you lose weight. 

Side effects of keto vs low fat 

In addition to their benefits, both also have some side effects, let's find out what they are.


Side effects of LF

Reduces the number of healthy fats in the diet

Several vitamins are fat-soluble, which means that they cannot be absorbed by the digestive system unless you consume fats in your diet in order to absorb them. These fat-soluble vitamins include A, D, E, and K. If you take too much fat out of your diet, you may have trouble absorbing these nutrients into your body.

Increases the intake of unhealthy foods

Since the low-fat approach was recommended by many health experts in the 1980s (and even before), food companies started to come out with low-fat alternatives to their products such as dairy, desserts, biscuits, cookies, etc. Despite being low in fat, these foods are loaded with sugar to replace the fat. In other words, these foods provide very little nutritional value in your diet and can make people falsely believe that if they eat low-fat, they are eating healthy.


Side effects of keto

Keto is a high-fat, low-carbohydrate eating approach that has been shown to have several health benefits, including weight loss and improved blood sugar control. However, there are also some potential drawbacks to this way of eating. One of the most common complaints about keto is that it can be difficult to stick to in the long term. This is because of the restricted nature of the diet. In addition, some people may find that they miss certain food groups, such as fruits and carbs, that are not typically included in keto. 

Lastly, it is important to note that keto can cause some initial side effects, such as fatigue, nausea, and headaches. These side effects are usually temporary and will resolve on their own as your body adjusts to the new way of eating. 


Keto vs low-fat diet foods  

In the following chart you'll see which foods are allowed or not allowed in both these eating regimes.

Beans and legumes In moderation Yes
Condiments and sauces Yes (low-carb) Yes
Dairy Yes (low-carb) Yes (low-fat)
Sugar-free drinks Yes Yes
Sugar-sweetened beverages No Yes
Alcoholic drinks Yes (low-carb) Yes
Eggs Yes Yes
Fish and seafood Yes Yes (low-fat)
Fruits Yes (in moderation) Yes
Grains and starches Yes (in moderation) Yes
Herbs and spices Yes Yes
Meat and poultry Yes Yes (low-fat)
Nuts and seeds Yes Limited
Oils and fats Yes Limited
Processed foods Yes (low-carb, in moderation) Yes (low-fat)
Sugar-free sweeteners Yes Yes
Natural sweeteners Yes (low-carb, in moderation) Yes
White and brown sugars No Yes
Starchy vegetables Yes (low carb, in moderation) Yes
Non-starchy vegetables Yes Yes

The main difference between the LF diet and the keto diet is that you have to limit your carbohydrates as part of the keto diet, while you have to restrict your fat intake on the LF diet. To take a closer look at whether specific ingredients are keto-approved, use the keto-friendly food checker.

Which is cheaper?

There are many factors to consider when choosing an eating plan, including cost, so which one is more affordable?

Generally speaking, the low-fat approach may be less expensive than keto. This is because carbohydrate rich foods are usually cheaper (like pasta or bread).

By contrast, some keto-friendly foods tend to be more expensive, such as avocados, nuts and seeds, and extra virgin olive oil. However, there are ways to do keto on a budget.

Of course, the cost is not the only consideration when choosing a diet. Both low-fat and keto diets can be healthy options depending on your individual needs and goals. However, if cost is a major factor in your decision-making process, a low-fat diet is likely the more affordable option.


Which one is healthier?

Depending on your food choices, both ways of eating can be part of a healthy balanced diet. 

But you can also make unhealthy choices on either plan. 

For example, while on a low-fat diet, if you choose to indulge excessively in processed food, this may have negative consequences on your health in the long term. For example, certain sweets are completely made from sugar, so they are fat free, but this doesn’t make them healthy!

Furthermore, products marketed as low-fat often contain large amounts of added sugar and other unhealthy additives. 

Meanwhile, on keto, you can also make unhealthy decisions while technically following the diet, like eating lots of processed meat and saturated fat.

So, picking healthier foods and moderating the intake of unhealthy ones is key in both these diets. 

As long as the majority of your diet consists of minimally processed whole foods, both diets can be deemed as healthy. Both diets will include varying amounts of fruits, vegetables, legumes, lean proteins, dairy, healthy plant fats and for low fat, wholegrains. 

Whatever you decide, you should remember that staying committed to your eating pattern over the long term is critical to your success in losing weight and maintaining a healthy lifestyle.