header image Gastric Sleeve article Heusschen

The true story on deficiencies after a Gastric Sleeve; results of a double-blind RCT with the first version of WLS Optimum

For a long time, professionals have stated that a Gastric Sleeve has minimal impact on the nutrient status. However, studies have found that deficiencies are as common after a Gastric Sleeve patients as after a Roux-en-Y Gastric Bypass. To prevent vitamin and mineral deficiencies, lifelong supplementation is recommended. In 2009, FitForMe developed a specialized multivitamin supplement specifically for Gastric Sleeve patients, based on scientific literature: The first version of WLS Optimum.

Serum blood values of WLS Optimum 1.0 versus standard multivitamin supplements

In a double-blind randomized controlled trial, the effectiveness of WLS Optimum 1.0 on deficiency prevention after a Gastric Sleeve was compared to a standard multivitamin supplement (sMVS). For 12 months, 69 Sleeve patients received WLS Optimum 1.0, whereas 70 Sleeve patients in the control group obtained sMVS. Serum blood values of the most common deficiencies were determined preoperatively, and at 6 and 12 months after surgery.

High deficiency rates after a Gastric Sleeve

This study illustrates that, despite common belief, nutritional deficiencies are highly prevalent after a Gastric Sleeve. Between groups, the prevalence of several nutritional deficiencies was comparable. Even though WLS Optimum 1.0 contained elevated doses of vitamins and minerals, the prevalence of micronutrient deficiencies remained high. WLS Optimum only significantly affected mean serum levels of folic acid, PTH and vitamin B1, and led to lower anemia rates compared to sMVS.

Low compliance

The relatively high deficiency levels may be explained by the low compliance. Even though WLS Optimum was provided free of charge, after one year about half of all patients was incompliant in their daily supplementation. Noncompliance with multivitamin supplements remains a key issue in the prevention of deficiencies and needs to be taken into consideration in post-operative advice.

The need for optimization of WLS Optimum 1.0

The results of this study clearly showed the importance of supplementation after a Gastric Sleeve and the need for further increase of the dosages of the first version of WLS Optimum, specifically for iron, folic acid, vitamin B12, vitamin D, vitamin B1 and zinc. The results of this and other studies have led to an optimization of WLS Optimum in December 2017.


Heusschen, L., Schijns, W., Ploeger, N. et al. The True Story on Deficiencies After Sleeve Gastrectomy: Results of a Double-Blind RCT. OBES SURG (2019) doi:10.1007/s11695-019-04252-1

Link to full text: https://link.springer.com/article/10.1007%2Fs11695-019-04252-1

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