By Adriana Ramos Calvo
What do you obtain when you crush, distill and ferment apples? One gets apple cider vinegar (ACV), which in the past was used as an antibiotic, to improve strength, and even for “detoxification”. This compound contains high levels of acetic acid, which might be responsible for its supposed benefits (5-6% as opposed to ordinary vinegar which contains about 4%). ACV has been thought to have healing properties for centuries and more recently has been marketed to aid with fat loss (Shmerling, 2018). There are also more extreme claims regarding apple cider vinegar in the world of alternative medicine, from improving digestion to reducing the risk of cancer. This article will explore whether there is scientific proof of the benefits of this vinegar on weight and body composition.
ACV, in addition to the acetic acid mentioned before, is mainly water since it contains little to no protein, fat or carbs and a small amount of potassium. One tablespoon provides between 8 and 11 mg of this component, which is only 0.2 to 0.3% of an adult’s daily dietary requirements (Hanan, n.d.). It also contains small amounts of antioxidants (Xia et al., 2020, Budak et al., 2014). Organic cold-pressed ACV contains ‘must’, crushed pieces of apple which makes the liquid cloudy in appearance. This must contains a substance called ‘the mother’ of vinegar, a combination of yeast and bacteria, and therefore this type of ACV can be considered a fermented food which contains probiotics (S. Johnston, 2019). Since the bacteria may not survive digestion, it is unclear whether this impacts the health of those who consume it (Hanan, n.d.).
Multiple studies showed that apple cider vinegar prevented fat deposition and metabolic improvement in mice and rats that suffered from obesity. The most important trial on humans, however, happened in 2009 and included 175 people who consumed 0, 1 or 2 tablespoons of vinegar daily. After three months of vinegar consumption, the subjects that had received the treatment showed lower triglyceride levels, as well as a modest weight loss of 2-4 pounds, as opposed to their counterparts. Another posterior study showed a reduction of appetite after vinegar consumption, but it also showed that it occurred by causing nausea. Neither of these studies, however, specifically studied ACV. For that matter, not many studies have been conducted focusing on the impact of ACV on weight loss. There has been some reported evidence, however, of vinegar in general promoting weight loss by affecting insulin function, metabolism, and appetite (Hernández et al., 2019). For example, a study from 2009 showed a reduction in appetite leading to a reduction in the caloric consumption when having ordinary vinegar with a meal, but this study did not monitor if this a further impact on weight over time (Johnston and Buller, 2005). Another trial conducted in Japan showed that obese adults who consumed one or two tablespoons of vinegar per day reported lower waist circumference, visceral fat and body weight (Kondo et al., 2009), while other animal studies also showed that acetic acid may help reduce body fat content (Hernández et al., 2019, Kondo et al., 2009). In a more recent investigation, 39 subjects were randomly assigned to follow a restricted calorie diet either with or without apple cider vinegar for 12 weeks. After this period, both groups reported weight loss, but the apple cider group lost more (4kg as opposed to 2.3kg) (Khezri et al., 2018).
In summary, most of the studies that have been conducted have been small and short-term. Overall, the evidence that vinegar consumption, regardless of the type leads to long-term fat loss is not compelling. Other studies suggest that vinegar can have other health benefits, like preventing spikes in blood sugar in patients diagnosed with prediabetes and type 2 diabetes through starch absorption blockage. Furthermore, other details of the supposedly beneficial consumption of ACV remain unclear, including when to drink it or how much to consume per day, among other questions (Hanan, n.d.). Something else to keep in mind is that the regular consumption of apple cider vinegar can have consequences, like for example teeth erosion due to its acidity (Richards, 2016) or burning of the skin and throat, especially in children (Hill et al., 2005). Furthermore, patients that suffer from diseases that slow gastric emptying (e.g., gastroparesis) may see their gut issues worsened by ACV consumption since it may delay the release of food from the stomach (Hlebowicz et al., 2007). All in all, even though there have been some interesting remarks in terms of vinegar and weight loss, there is a lack of human data, especially regarding studies focusing specifically on apple cider vinegar (Hanan, n.d.) and its possible side effects.
References:
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Imperial Bioscience Review 