So a cookie diet may be good for me?

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As we enter the holiday season, indulgence and good cheer is in high demand. Inevitably, the post-holiday hangover brings with it grandiose plans to get in better shape, eat better and improve health overall.  And readily waiting to support all these good intentions are hordes of diet books, diet plans and exercise equipment that, if the promises are to believed, put us one step closer to achieving our fitness and health goals.

New medical research, however, raises some interesting questions that may have profound implications for the diet industry. Researchers at the Weizmann Institute of Science in Israel studied the blood glucose response of 800 subjects.  In effect, what they discovered was that the same piece of Christmas cake could have different impact on the blood sugar response of different individuals.[1] The exact same food could cause huge blood sugar spikes in some people but next to no change in others. Even more interestingly, different foods had different impacts on different people. For example, one participant reacted strongly to bananas while another reacted strongly to cookies.[2]

According to Eran Segal, one of the authors of the study, “For many years, our thinking has been that people develop obesity, diabetes and other diet-related diseases because they are not compliant with our dietary advice. However, based on our study, another possibility is that people are, in fact, compliant but that the dietary advice that we are giving them is inappropriate. Thus, … we believe that a take-home message for people from our work is that if a diet did not work for you, it may be the diet's fault and not your fault.”[3]

So, the authors conclude that a one-size fits all diet is not appropriate for most people. After considering over 130 factors, including the nutrient content of a meal but, perhaps more importantly, the traits of the person eating it, Segal and his fellow researchers believe that diets can be personalized to the needs of the individual.

Like dieting, investing should be customized to the individual

In a similar vein, a one-size fits all investment portfolio is not appropriate for most people.  In constructing an investment portfolio to meet the needs of an individual, consideration has to be given to the multiple goals that individual investors usually have. Take the typical, but hypothetical example, of John and Maria Lee, a married couple in their early 40s with two young children. Their financial goals include (i) saving for their retirement in twenty-five years, (ii) funding their children’s university education in fifteen years and (iii) saving for a larger home in five years. Each of these goals needs to be understood in the same way as one of Segal’s study participants – bananas may work for one and cookies for the other. The bottom line is that the same approach cannot be taken for each goal.

This is exactly what goals-based investing (GBI), an approach that Manulife Private Wealth pioneered in Canada when it launched its goals-based investment platform in 2012, is designed to do: GBI personalizes investment strategy to individual investors and their various goals. It reflects the fact that each person has different goals and that each goal has a different time horizon, a different consequence of success and failure and therefore a different level of priority for that person. To treat these goals all the same is the equivalent of the one-size fits all nutrition advice that Segal says doesn’t work in controlling blood sugar.

Constructing a goals-based investment strategy is just the tip of the iceberg. Implementing a differentiated strategy depending on goals, monitoring it and then reporting performance by goals is what allows for a truly personalized investment strategy.  It stands to reason that if a personalized diet is needed to achieve an individual’s health goals, that a personalized investment strategy is also needed to achieve an individual’s financial goals.


Read my previous post China’s growth still strong: a closer look at the numbers.


[1] Zeevi, David, et al. "Personalized Nutrition by Prediction of Glycemic Responses." Cell 163.5 (2015): 1079-1094.


[2] The Algorithm that Creates Diets that Work for You,