What is really cool about this recent study from Akbaraly et al is not what they found but what they were looking for and how they defined those things (the constructs).
Here is the citation:
Akbaraly, T., Sabia, S., Hagger-Johnson, G., Tabak, A. G., Shipley, M. J., Jokela, M.,  Kivimaki, M. (2013). Does Overall Diet in Midlife Predict Future Aging Phenotypes? A Cohort Study. The American Journal of Medicine, 126(5), 411-419.e413.
And you can see the study summary abstract by clicking here  

   My goal today is to explain the variables they used and the assumptions behind them such that you might consider your lifestyle in the same context.
   The researchers wanted to see if a persons diet pattern and score on the Alternative Healthy Eating Index (AHEI) in mid life - 30 to 60 years old, impacted how they aged, beginning at age 60.  First of all, seeing a study that used the AHEI made me happy and the index should sound familiar to you.  See past posts and a good explanation of the system that scores your diet's quality here.

   Akbaraly et al studied more than 5000 adults.  At one time during the 16 years of study, they asked the participants to complete a food frequency questionnaire (FFQ).  They used a statistical program to assign people to one of two dietary patterns based on their FFQ.  They also  gave them a score on the AHEI.  The two dietary patterns were "Healthy Foods" and "Western Type".  You might already guess that the Healthy Foods group also scored best on the AHEI. 
   The Healthy Foods group consumed more fruits and vegetables, whole grains, and fish while the Western Type group consumed more fried foods, processed food and red meat, plus pies, sweetened desserts, chocolates, refined grains, high-fat dairy products, and condiments (like that crazy fattening mayonnaise!).  

   You can consider the diet patterns the predictors.  What do they predict?  The type of aging one might experience.

   The researchers created 5 categories of aging.and assigned people to one of them at the end of the study (2007-2009). The first is IDEAL aging, next is where a person has nonfatal heart and circulation diseases, then fatal heart and circulation disease (i.e., the person died from heart attack or stroke before 2007), the fourth type is death from another cause, and the fifth is referred to as usual or natural aging - these people have the usual chronic diseases (e.g., heart disease, diabetes, cancer) that are NOT really normal as in many cases they could have been prevented.

   The Healthy Foods diet was associated with better health and functioning in older age.  A high score on the AHEI reduced the chances of dying too soon.  A premature death is one that  occurs before age 75 in most high income countries.  (BTW -In this study they concentrated on the diet and 'made like' everyone weighed the same and exercised the same).

   But don't you most want to know what it means to have aged Ideally?  I will tell you - as I am well on my way of doing just that thing :)  - knock on wood please.

At the end of the study, the ideal agers:
1)  were alive, and
2)  did not have any chronic diseases (e.g., diabetes (or blood sugar levels requiring medicine), cancer, coronary (heart) disease, or stroke risk/history, or 
3) mental health problems (determined by responses to  questions on a trusted survey)
4) had good thinking and memory skills (they were tested for this - including word recall and basic math), and
5) normal blood sugar levels (for ones age and sex), and
6) good lung function (for age and sex), tested with the forced expiratory volume (FeV1) Remember that?  See this post.
7) had normal or above normal walking speed for age and sex

   There are things that happen to us when we get older that we have no control over - like our hair turns grey or gets thinner, we get some wrinkles and age spots (more if we don't take care of our skin), but disease in old age is NOT inevitable - you can reduce your chances of some of the 'usual' diseases of aging by eating well and exercising - NOW.

   Remember too, it's only a healthy lifestyle if you engage in it everyday - and it only helps you as long as you do it (minor and infrequent indulgences allowed :))