Is drinking oil an effective method for reducing body fat?

Drinking Oil Does Not Reduce Body Fat and May Cause Weight Gain

Drinking oil is not an effective method for reducing body fat; in fact, consuming oil in excess contributes to weight gain due to its high caloric density at 9 kcal/g. 1

Why This Practice Is Ineffective

Caloric Density Makes Weight Loss Unlikely

• Fat contains more than twice the calories per gram (9 kcal/g) compared to carbohydrates and protein (4 kcal/g), making it the most energy-dense macronutrient 1
• A high-quality systematic review showed probable evidence for a moderate direct association between total fat intake and body weight 1
• Weight loss requires creating an energy deficit; adding calorie-dense oil works against this fundamental principle 1

Evidence Shows Fat Intake Increases Weight

• Fried food consumption was positively associated with risk of weight gain, though oil type may modify this association 1
• Butter consumption is associated with modestly greater long-term weight gain 1
• The Women's Health Initiative trial demonstrated that lowering total dietary fat among nearly 50,000 women showed no benefits for weight management 1

The Type of Oil Matters, But None Promote Fat Loss When Consumed in Excess

Oils Associated With Weight Gain

• Soybean, palm, and sunflower oils were associated with weight gain in a network meta-analysis of randomized controlled trials 2
• Palm oil ranked lowest for weight reduction (SUCRA value = 0.2) 2

Oils That May Be Weight-Neutral or Slightly Beneficial

• High olive oil intake was neither negatively nor positively associated with increased risk of becoming overweight or obese 1
• A diet enriched with olive oil reduced weight more than control diet by -0.92 kg (95% CI: -1.16, -0.67), but only when incorporated as part of an overall dietary pattern, not consumed in isolation 3
• Sesame oil had the highest ranking for reducing weight (SUCRA value = 0.9) in network meta-analysis, but this was in the context of controlled dietary interventions 2
• Medium-chain triglyceride (MCT) oil consumption as part of a weight-loss program resulted in greater weight loss (-1.67 kg) compared to olive oil, but only when combined with energy restriction and counseling 4, 5

The Critical Context: Dietary Pattern Matters More Than Individual Foods

Quality Over Quantity

• Current dietary guidelines emphasize the quality, rather than the quantity, of dietary fats 1
• The 2015 Dietary Guidelines Advisory Committee states that dietary guidelines should not focus on lowering total fat, recognizing that low-fat diets have no benefits for major chronic diseases 1
• Virgin oils (extra-virgin olive oil, virgin soybean oil) may be preferable due to their low-temperature refinement that preserves trace phenolic compounds 1

Oils Must Replace Less Healthy Foods, Not Add Calories

• The current evidence supports generally increased consumption of vegetable oils in place of refined grains, starches, sugars, meats, butter, and lard—not in addition to them 1
• In the PREDIMED trial, participants receiving extra-virgin olive oil experienced 30% lower risk of cardiovascular events, but about 60% of the oil simply replaced regular olive oil already in the diet 1

Common Pitfall: Misunderstanding "Healthy Fats"

The misconception that drinking oil reduces fat likely stems from confusion about "healthy fats" in the diet. While certain oils like extra-virgin olive oil have cardiovascular benefits, these benefits occur when:

• The oil is part of an overall healthy dietary pattern (like the Mediterranean diet) 1
• Total caloric intake remains controlled 1, 5
• The oil replaces less healthy fats or refined carbohydrates 1

Simply adding oil to the diet without reducing other caloric sources will result in weight gain, not weight loss 1

Practical Recommendation

If weight loss is the goal, focus on creating a caloric deficit through:

• Matching or reducing total energy intake relative to energy expenditure 1
• Emphasizing whole foods including fruits, vegetables, whole grains, legumes, nuts, and fish 1
• Using modest amounts of high-quality oils (extra-virgin olive oil, canola oil) to replace saturated fats and refined carbohydrates, not as additional calories 1
• Avoiding the practice of drinking oil, which adds concentrated calories without satiety benefits 1