The concept of health and nutrition has evolved significantly in the last few decades. This evolution is not only driven by scientific revelations but also by the digital revolution that has been engulfing the world. Traditional face-to-face meetings with nutritionists are increasingly being replaced by online consultations. This shift has been gradual yet profound, and its implications extend beyond convenience. It revamps our perception of health, well-being, and the methods by which we obtain them.

Predictive analytics and artificial intelligence (AI) are at the forefront of this transformation. Predictive analytics involves the use of data, statistical algorithms, and machine learning techniques to identify future outcomes based on historical data. In the field of nutrition, this could lead to personalized dietary charts based on consumption patterns or the anticipation of potential health issues. AI, on the other hand, can analyze vast amounts of data in the blink of an eye, providing insights that would take humans months to deduce.

Novel as it may seem, the application of AI in nutrition is not unfounded. The science of nutrition is an intricate web of variables including genetics, lifestyle, environment, and personal taste preferences. AI, with its capacity to analyze these multifaceted variables, can work towards creating a highly personalized nutrition plan. This algorithmically derived nutrition advice could be more effective and efficient than traditional methods.

Online nutritionists, equipped with these technologies, could redefine diet plans and food habits. However, it's crucial to examine the implications of this shift in relation to the principles of information privacy and patient autonomy. In an era where personal data is a highly valued commodity, the collection and analysis of health data could potentially compromise the privacy of individuals. Similarly, while AI can provide valuable insights, the final decision must always rest with the individual, ensuring patient autonomy.

The advent of wearable technology and Internet of Things (IoT) devices further complements the rise of online nutritionists. These devices can monitor vital health parameters in real-time, providing valuable data to the nutritionist. This constant stream of information can enable an ongoing relationship between the nutritionist and the patient, fostering an environment of continuous care and well-being.

While we envision a future with technologically advanced online nutritionists, we must also consider the potential social and economic implications. By bringing nutritionists to the digital realm, we break the geographical barriers, making expert advice accessible to individuals in remote areas. Furthermore, the reduced cost of online consultations compared to traditional appointments can democratize access to nutrition advice. However, it also creates a digital divide, excluding those who lack access to technology.

As we move into this new era, it will be essential to navigate these challenges carefully. Online nutritionists can revolutionize the field of nutrition, but it must be done in a way that respects privacy, autonomy, and equality.

In conclusion, the future of online nutritionists looks promising but complex. Technological advancements like AI, predictive analytics, and IoT devices can catalyze a paradigm shift. However, we need to tread carefully, ensuring that this shift is ethical, equitable, and truly beneficial for all.