Healthy Meal Replacement Smoothies: How to Make Them Delicious and Nutritious

How can Meal Replacement shakes be a nutritious option?

Meal replacements are foods or beverages that are used to replace one or more meals in order to reduce your overall calorie consumption for the purpose of weight loss or weight maintenance after losing weight. Soups, shakes, bars, and portion-controlled ready-made meals are all examples of meal replacements.

So, are meal replacement shakes a healthy and effective way to lose weight? To help us answer this issue for this post, I looked at the evidence from a 2018 systematic review and meta-analysis on the effectiveness of meal replacements for weight loss conducted by Oxford University in the United Kingdom. A systematic review is a high-quality study that examines all available information and then re-analyses the data as if it were one major study to increase confidence in the findings.

The study included data from 23 trials involving nearly 8000 participants. According to the findings of this study, meal replacement products result in an additional 1.5kg weight loss after one year when compared to dieting alone. The study also found that the difference in weight loss lasted for up to four years.  

Many people are likely to believe this isn't a lot of weight reduction, but data and experience show that a goal of 5-10% weight loss over a year is actually what is  realistic when implementing diet and exercise modifications.  This means that a 90kg woman may possibly lose 5-9kg in a year. So an extra 1.5kg over a year might make a significant difference for many people. 

So, what exactly is in a meal replacement shake, and what nutrition does it provide? A meal replacement should ideally provide a nutritional balance as well as appropriate protein, energy, and a small amount of fat. These final three nutrients are all classified as macronutrients. These are our primary sources of energy in food, and they all serve different purposes and perform different tasks in the body.

Protein is the primary source of amino acids in our bodies.  Proteins are involved whenever the body is growing, mending, or replacing tissue. Proteins are also required for the replacement of dead or damaged cells. A skin cell has a life span of roughly 30 days. As old skin cells shed, new protein-rich cells sprout from beneath to replace them. Deeper skin layers cells produce new proteins for hair and fingernails. In reaction to exercise, muscle cells produce new proteins that allow them to become larger and stronger. Every several days, gastrointestinal tract cells are replaced. The body then continuously deposits protein into new cells that replace those that have been lost, both inside and outside the body. Considering that hormones and enzymes are also made up of protein, it is clear that protein is critically important for life! 

However, this does not imply that more is better. The amount of protein that the body can absorb and use at any given meal is limited. Around 20-25g of protein is regarded to be the sweet spot, therefore any meal replacement must match this requirement.

Protein also has the added benefit of slowing the release of food from the stomach, which helps you feel fuller for a longer period of time. And when you're eating less, this is a significant factor.

Carbohydrates, which are broken down into single molecules of glucose, are another necessary macronutrient. Glucose is like fuel for your body; it is the primary source of energy for all cells (including the brain). If you are deficient in this nutrient, you may experience a lack of 'va va voom'. So a meal replacement with some carbohydrates is necessary to keep your brain and body functioning optimally. The amount of carbohydrates will vary, and you may discover that more is better than less (or vice versa), so it is something you can experiment with. It's important to remember that 15g of carbohydrates equals around 1 slice of bread. So, consider how many carbs you would normally consume to feel satiated and use it as a starting point when looking at meal replacement options to avoid feeling flat.